Configuration Examples for BFD

NE20E-S V800R012C00SPC300 Configuration Guide - Network Reliability 04

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This section provides BFD configuration examples.

Example for Configuring Single-Hop BFD for a Layer 3 Eth-Trunk
Example for Configuring BFD to Monitor VPN Routes
Example for Configuring BFD for Static VPN Routes
Example for Configuring Multi-hop BFD
Example for Configuring Single-hop BFD for IPv6
Example for Configuring Multi-hop BFD for IPv6
Example for Configuring Sub-Interfaces for QinQ VLAN Tag Termination to Support BFD
Example for Configuring Sub-Interfaces for Dot1q VLAN Tag Termination to Support BFD
Example for Configuring a BFD for Link-Bundle Session to Detect Layer 3 Eth-Trunk Member Link Faults
Example for Configuring a BFD for Link-Bundle Session to Detect Layer 3 Eth-Trunk Member Link Faults (IPv6)
Example for Configuring a One-Arm BFD Echo Session
Example for Configuring the Delay of a BFD Session to Go Up
Example for Associating a BFD Session with an Interface
Example for Associating a BFD Session and a Sub-interface
Example for Enabling BFD to Modify the PST
Example for Configuring Static BFD for TE with Automatically Negotiated Discriminators

Example for Configuring Single-Hop BFD for a Layer 3 Eth-Trunk

This section provides an example for establishing single-hop BFD sessions on Eth-Trunk interfaces to monitor the directly connected link between the Eth-Trunk interfaces.

Networking Requirements

Eth-Trunks enhance link reliability. BFD sessions are established to rapidly monitor Eth-Trunks. As shown in Figure 3-5, the Eth-Trunk connecting Device A and Device B consists of two GE links.

This example requires BFD to be performed over the Eth-Trunk.

Figure 3-5 Single-hop BFD for a Layer 3 Eth-Trunk

Interfaces 1 through 2 in this example are GE 0/1/0, GE 0/2/0, respectively.

Precautions

BFD sessions must be established on the Eth-Trunk interface of both the local and remote devices.

Configuration Roadmap

The configuration roadmap is as follows:

Create an Eth-Trunk interface on both the local and remote devices.
Configure single-hop BFD for the Eth-Trunk.

Data Preparation

To complete the configuration, you need the following data:

Local Eth-Trunk interface that sends and receives BFD control packets
Peer IP address monitored by BFD (the IP address of the Eth-Trunk interface)
Names of the BFD sessions for monitoring the Eth-Trunk
Local and remote discriminators of BFD sessions

Procedure

Configure an Eth-Trunk interface.

# Create an Eth-Trunk interface on Device A and set the lower threshold of the Eth-Trunk in the Up state to 1.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceA

[*HUAWEI] commit

[~DeviceA] interface eth-trunk 1

[*DeviceA-Eth-Trunk1] undo shutdown

[*DeviceA-Eth-Trunk1] ip address 10.1.1.1 24

[*DeviceA-Eth-Trunk1] least active-linknumber 1

[*DeviceA-Eth-Trunk1] commit

[~DeviceA-Eth-Trunk1] quit

[~DeviceA] interface gigabitethernet 0/1/0

[~DeviceA-Gigabitethernet0/1/0] undo shutdown

[*DeviceA-Gigabitethernet0/1/0] eth-trunk 1

[*DeviceA-Gigabitethernet0/1/0] commit

[~DeviceA-Gigabitethernet0/1/0] quit

[~DeviceA] interface gigabitethernet 0/2/0

[~DeviceA-Gigabitethernet0/2/0] undo shutdown

[*DeviceA-Gigabitethernet0/2/0] eth-trunk 1

[*DeviceA-Gigabitethernet0/2/0] commit

[~DeviceA-Gigabitethernet0/2/0] quit

# Create an Eth-Trunk interface on Device B and set the lower threshold of the Eth-Trunk in the Up state to 1.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceB

[*HUAWEI] commit

[~DeviceB] interface eth-trunk 1

[*DeviceB-Eth-Trunk1] undo shutdown

[*DeviceB-Eth-Trunk1] ip address 10.1.1.2 24

[*DeviceB-Eth-Trunk1] least active-linknumber 1

[*DeviceB-Eth-Trunk1] commit

[~DeviceB-Eth-Trunk1] quit

[~DeviceB] interface gigabitethernet 0/1/0

[~DeviceB-Gigabitethernet0/1/0] undo shutdown

[*DeviceB-Gigabitethernet0/1/0] eth-trunk 1

[*DeviceB-Gigabitethernet0/1/0] commit

[~DeviceB-Gigabitethernet0/1/0] quit

[~DeviceB] interface gigabitethernet 0/2/0

[~DeviceB-Gigabitethernet0/2/0] undo shutdown

[*DeviceB-Gigabitethernet0/2/0] eth-trunk 1

[*DeviceB-Gigabitethernet0/2/0] commit

[~DeviceB-Gigabitethernet0/2/0] quit

After completing the configurations, run the display interface eth-trunk command on Device A or Device B. The command output shows that the interface status is Up.

The following example uses the command output on Device A.

[~DeviceA] display interface eth-trunk 1

Eth-Trunk1 current state : UP (ifindex: 19)
Line protocol current state : UP
Last line protocol up time : 2010-08-04 08:34:41
Description: HUAWEI, Quidway Series, Eth-Trunk1 Interface 
Route Port,Hash arithmetic : According to flow,Maximal BW: 100M, Current BW: 100
M, The Maximum Transmit Unit is 1500
Internet Address is 10.1.1.1/24
IP Sending Frames' Format is PKTFMT_ETHNT_2, Hardware address is 38db-1520-0100
Current system time: 2010-08-04 08:35:02
Physical is ETH_TRUNK
    Last 300 seconds input rate 0 bits/sec, 0 packets/sec
    Last 300 seconds output rate 0 bits/sec, 0 packets/sec
    Realtime 0 seconds input rate 0 bits/sec, 0 packets/sec
    Realtime 0 seconds output rate 0 bits/sec, 0 packets/sec
    Input: 0 packets,0 bytes,
           0 unicast,0 broadcast,0 multicast
           0 errors,0 drops,
    Output:0 packets,0 bytes,
           0 unicast,0 broadcast,0 multicast
           0 errors,0 drops
    Last 300 seconds input utility rate:  0.00%
    Last 300 seconds output utility rate: 0.00%

-----------------------------------------------------
PortName                Status              Weight
-----------------------------------------------------
Gigabitethernet0/1/0    UP                  1
Gigabitethernet0/2/0    UP                  1
-----------------------------------------------------
The Number of Ports in Trunk : 2
The Number of UP Ports in Trunk : 2

The Eth-Trunk interfaces on Device A and Device B can ping each other.

The following example uses the command output on Device A.

[~DeviceA] ping -a 10.1.1.1 10.1.1.2

  PING 10.1.1.2: 56  data bytes, press CTRL_C to break

    Reply from 10.1.1.2: bytes=56 Sequence=1 ttl=255 time=31 ms

    Reply from 10.1.1.2: bytes=56 Sequence=2 ttl=255 time=31 ms

    Reply from 10.1.1.2: bytes=56 Sequence=3 ttl=255 time=62 ms

    Reply from 10.1.1.2: bytes=56 Sequence=4 ttl=255 time=62 ms

    Reply from 10.1.1.2: bytes=56 Sequence=5 ttl=255 time=62 ms

  --- 10.1.1.2 ping statistics ---

    5 packet(s) transmitted

    5 packet(s) received

    0.00% packet loss

    round-trip min/avg/max = 31/49/62 ms

Configure single-hop BFD for the Eth-Trunk.

# Enable BFD on Device A and establish a BFD session to monitor the link from Device A to Device B. Bind the BFD session to the Eth-Trunk interface.

[~DeviceA] bfd

[*DeviceA-bfd] quit

[*DeviceA] bfd atob bind peer-ip 10.1.1.2 interface eth-trunk 1

[*DeviceA-bfd-session-atob] discriminator local 10

[*DeviceA-bfd-session-atob] discriminator remote 20

[*DeviceA-bfd-session-atob] commit

[~DeviceA-bfd-session-atob] quit

# Enable BFD on Device B and establish a BFD session to monitor the link from Device B to Device A. Bind the BFD session to the Eth-Trunk interface.

[~DeviceB] bfd

[*DeviceB-bfd] quit

[*DeviceB] bfd btoa bind peer-ip 10.1.1.1 interface eth-trunk 1

[*DeviceB-bfd-session-btoa] discriminator local 20

[*DeviceB-bfd-session-btoa] discriminator remote 10

[*DeviceB-bfd-session-btoa] commit

[~DeviceB-bfd-session-btoa] quit

Verify the configuration.

After completing the configurations, run the display bfd session all verbose command on Device A and Device B. The command output shows that a single-hop BFD session has been established and its status is Up.

The following example uses the command output on Device A.

[~DeviceA] display bfd session all verbose

(w): State in WTR  (*): State is invalid
------------------------------------------------------------------------------
   (One Hop) State : Up                       Name : atob
------------------------------------------------------------------------------
  Local Discriminator    : 10               Remote Discriminator    : 20
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(Eth-Trunk1)
  Bind Session Type      : Static
  Bind Peer IP Address   : 10.1.1.2
  Bind Interface         : Eth-Trunk1
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255  
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : 2584985432       Session Detect TmrID   : -
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------
       Total UP/DOWN Session Number : 1/0

# Run the shutdown command on GE 0/1/0 of Device A to simulate a link fault.

[~DeviceA] interface gigabitethernet 0/1/0

[~DeviceA-Gigabitethernet0/1/0] shutdown

[*DeviceA-Gigabitethernet0/1/0] commit

[~DeviceA-Gigabitethernet0/1/0] quit

Run the display bfd session all verbose and display interface eth-trunk commands on Device A and Device B. The command output shows that the statuses of the BFD session and Eth-Trunk interface are still Up.

The following example uses the command output on Device A.

[~DeviceA] display bfd session all verbose

(w): State in WTR  (*): State is invalid
--------------------------------------------------------------------------------
(One Hop) State : Up                        Name : atob
------------------------------------------------------------------------------
  Local Discriminator    : 10              Remote Discriminator   : 20
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(Eth-Trunk1)
  Bind Session Type      : Static
  Bind Peer IP Address   : 10.1.1.2
  Bind Interface         : Eth-Trunk1
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255  
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : Control Detection Time Expired
  Bind Application       : No Application Bind
  Session TX TmrID       : 2584985432       Session Detect TmrID   : -
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------
Total UP/DOWN Session Number : 1/0

[~DeviceA] display interface eth-trunk 1

Eth-Trunk1 current state : UP
Line protocol current state : UP
Description : HUAWEI, Quidway Series, Eth-Trunk1 Interface, Route Port
Hash arithmetic : According to flow,Maximal BW: 200M, Current BW: 0M
The Maximum Transmit Unit is 1500 bytes
Internet Address is 10.1.1.1/24
IP Sending Frames' Format is PKTFMT_ETHNT_2, Hardware address is 00e0-fc12-7890
Physical is ETH_TRUNK
Last 300 seconds input rate 0 bits/sec, 0 packets/sec
    Last 300 seconds output rate 0 bits/sec, 0 packets/sec
    Realtime 0 seconds input rate 0 bits/sec, 0 packets/sec
    Realtime 0 seconds output rate 0 bits/sec, 0 packets/sec
    Input: 0 packets,0 bytes,
           0 unicast,0 broadcast,0 multicast
           0 errors,0 drops,0 unknownprotocol
    Output:0 packets,0 bytes,
           0 unicast,0 broadcast,0 multicast
           0 errors,0 drops
-----------------------------------------------------
PortName                Status              Weight
-----------------------------------------------------
Gigabitethernet0/1/0    DOWN                1
Gigabitethernet0/2/0    UP                  1
-----------------------------------------------------
The Number of Ports in Trunk : 2
The Number of UP Ports in Trunk : 1

Run the shutdown command on GE 0/2/0 of Device A to simulate a link fault.

[~DeviceA] interface gigabitethernet 0/2/0

[~DeviceA-Gigabitethernet0/2/0] shutdown

[*DeviceA-Gigabitethernet0/2/0] commit

[~DeviceA-Gigabitethernet0/2/0] quit

The following example uses the command output on Device A.

[~DeviceA] display bfd session all verbose

(w): State in WTR  (*): State is invalid
------------------------------------------------------------------------------
   (One Hop) State : Down                       Name : atob
------------------------------------------------------------------------------
  Local Discriminator    : 10               Remote Discriminator    : 20
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(Eth-Trunk1)
  Bind Session Type      : Static
  Bind Peer IP Address   : 10.1.1.2
  Bind Interface         : Eth-Trunk1
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255  
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : 2584985432       Session Detect TmrID   : -
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------
       Total UP/DOWN Session Number : 0/1

[~DeviceA] display interface eth-trunk 1

Eth-Trunk1 current state : DOWN
Line protocol current state : DOWN
Description : HUAWEI, Quidway Series, Eth-Trunk1 Interface, Route Port
Hash arithmetic : According to flow,Maximal BW: 200M, Current BW: 0M
The Maximum Transmit Unit is 1500 bytes
Internet Address is 10.1.1.1/24
IP Sending Frames' Format is PKTFMT_ETHNT_2, Hardware address is 00e0-4b0c-f700
Physical is ETH_TRUNK
Last 300 seconds input rate 0 bits/sec, 0 packets/sec
    Last 300 seconds output rate 0 bits/sec, 0 packets/sec
    Realtime 0 seconds input rate 0 bits/sec, 0 packets/sec
    Realtime 0 seconds output rate 0 bits/sec, 0 packets/sec
    Input: 0 packets,0 bytes,
           0 unicast,0 broadcast,0 multicast
           0 errors,0 drops,0 unknownprotocol
    Output:0 packets,0 bytes,
           0 unicast,0 broadcast,0 multicast
           0 errors,0 drops
-----------------------------------------------------
PortName                Status              Weight
-----------------------------------------------------
Gigabitethernet0/1/0    DOWN                1
Gigabitethernet0/2/0    DOWN                1
-----------------------------------------------------
The Number of Ports in Trunk : 2
The Number of UP Ports in Trunk : 0

Configuration Files

Device A configuration file

 sysname DeviceA

bfd

interface Eth-Trunk1

 ip address 10.1.1.1 255.255.255.0

interface Gigabitethernet0/1/0

 undo shutdown

 eth-trunk 1

interface Gigabitethernet0/2/0

 undo shutdown

 eth-trunk 1

bfd atob bind peer-ip 10.1.1.2 interface Eth-Trunk 1

 discriminator local 10

 discriminator remote 20

return

Device B configuration file

 sysname DeviceB

bfd

interface Eth-Trunk1

 ip address 10.1.1.2 255.255.255.0

interface Gigabitethernet0/1/0

 undo shutdown

 eth-trunk 1

interface Gigabitethernet0/2/0

 undo shutdown

 eth-trunk 1

bfd btoa bind peer-ip 10.1.1.1 interface Eth-Trunk 1

 discriminator local 20

 discriminator remote 10

return

Example for Configuring BFD to Monitor VPN Routes

This section provides an example for configuring BFD to monitor VPN routes.

Networking Requirements

As shown in Figure 3-6:

CE1 and CE2 belong to VPN-A and access the MPLS backbone network through PE1 and PE2, respectively.
GE 0/1/0 of PE1 and GE 0/1/0 of PE2 are bound to VPN-A.
BFD in asynchronous mode is used to monitor the VPN route between PE1 and PE2.

Figure 3-6 BFD for VPN routes

Interfaces 1 and 2 in this example represent GE 0/1/0 and GE 0/2/0, respectively.

Configuration Roadmap

The configuration roadmap is as follows:

Configure a BFD session on PE1 to monitor the multi-hop path from PE1 to PE2.
Configure a BFD session on PE2 to monitor the multi-hop path from PE2 to PE1.

Data Preparation

To complete the configuration, you need the following data:

Peer IP address monitored by BFD
BFD session names
Local and remote discriminators of BFD sessions

Procedure

Assign an IP address to each interface. For configuration details, see Configuration Files in this section.
Configure the MPLS backbone network to interconnect PE1 and PE2. For configuration details, see Configuration Files in this section.
Configure a VPN instance. For configuration details, see Configuration Files in this section.

Configure the route between PE1 and PE2 to be reachable. For configuration details, see Configuration Files in this section.

After the configurations are complete, PE1 can ping the IP address of GE 0/1/0 on PE2.

<PE1> ping -vpn-instance vpna 10.2.1.2

  PING 10.2.1.2: 56  data bytes, press CTRL_C to break

    Reply from 10.2.1.2: bytes=56 Sequence=1 ttl=254 time=60 ms

    Reply from 10.2.1.2: bytes=56 Sequence=2 ttl=254 time=50 ms

    Reply from 10.2.1.2: bytes=56 Sequence=3 ttl=254 time=50 ms

    Reply from 10.2.1.2: bytes=56 Sequence=4 ttl=254 time=60 ms

    Reply from 10.2.1.2: bytes=56 Sequence=5 ttl=254 time=50 ms

  --- 10.2.1.2 ping statistics ---

    5 packet(s) transmitted

    5 packet(s) received

    0.00% packet loss

    round-trip min/avg/max = 50/54/60 ms

Configure BFD to monitor the VPN route between PE1 and PE2.

# Enable BFD on PE1, establish a BFD session with PE2, and bind the session to the VPN instance.

[~PE1] bfd

[*PE1-bfd] quit

[*PE1] bfd 1to2_vpn bind peer-ip 10.2.1.2 vpn-instance vpna

[*PE1-bfd-session-1to2_vpn] discriminator local 12

[*PE1-bfd-session-1to2_vpn] discriminator remote 21

[*PE1-bfd-session-1to2_vpn] commit

[~PE1-bfd-session-1to2_vpn] quit

# Enable BFD on PE2, establish a BFD session with PE1, and bind the session to the VPN instance.

[~PE2] bfd

[*PE2-bfd] quit

[*PE2] bfd 2to1_vpn bind peer-ip 10.1.1.2 vpn-instance vpna

[*PE2-bfd-session-2to1_vpn] discriminator local 21

[*PE2-bfd-session-2to1_vpn] discriminator remote 12

[*PE2-bfd-session-2to1_vpn] commit

[~PE2-bfd-session-2to1_vpn] quit

Verify the configuration.

After completing the configurations, run the display bfd session peer-ip vpn-instance vpn-name verbose command on PE1 and PE2. The command output shows that a multi-hop BFD session has been established and its status is Up.

The following example uses the command output on PE1.

<PE1> display bfd session peer-ip 10.2.1.2 vpn-instance vpna verbose

(w): State in WTR 
(*): State is invalid
--------------------------------------------------------------------------------
(Multi Hop) State : Up                        Name : 1to2_vpn
------------------------------------------------------------------------------
  Local Discriminator    : 12              Remote Discriminator   : 21
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Peer Ip Address
  Bind Session Type      : Static
  Bind Peer IP Address   : 10.2.1.2
  Bind Interface         : -
  Vpn Instance Name      : vpna
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 4784             TTL                    : 255  
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : -                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : -                Session Detect TmrID   : -
  Session Init TmrID     : -                Session WTR TmrID      : -
  PDT Index              : FSM-0|RCV-0|IF-0|TOKEN-0
  Session Description    : -
------------------------------------------------------------------------------
     Total UP/DOWN Session Number : 1/0

Configuration Files

PE1 configuration file

 sysname PE1

ip vpn-instance vpna

 route-distinguisher 100:1

 apply-label per-instance

 vpn-target 111:1 export-extcommunity

 vpn-target 111:1 import-extcommunity

bfd

 mpls lsr-id 1.1.1.1

 mpls

mpls ldp

interface gigabitethernet0/1/0

 undo shutdown

 ip binding vpn-instance vpna

 ip address 10.1.1.2 255.255.255.0

interface GigabitEthernet0/2/0

 undo shutdown

 ip address 172.16.1.1 255.255.255.0

 mpls

 mpls ldp

interface LoopBack1

 ip address 1.1.1.1 255.255.255.255

bgp 100

 peer 3.3.3.3 as-number 100

 peer 3.3.3.3 connect-interface LoopBack1

 ipv4-family unicast

  undo synchronization

  peer 3.3.3.3 enable

 ipv4-family vpnv4

  policy vpn-target

  peer 3.3.3.3 enable

 ipv4-family vpn-instance vpna

  peer 10.1.1.1 as-number 65410

  import-route direct

ospf 100

area 0.0.0.0

  network 1.1.1.1 0.0.0.0

  network 172.16.1.0 0.0.0.255

bfd 1to2_vpn bind peer-ip 10.2.1.2 vpn-instance vpna

 discriminator local 12

 discriminator remote 21

return

PE2 configuration file

sysname PE2

ip vpn-instance vpna

 route-distinguisher 200:1

 apply-label per-instance

 vpn-target 111:1 export-extcommunity

 vpn-target 111:1 import-extcommunity

bfd

 mpls lsr-id 3.3.3.3

 mpls

mpls ldp

interface GigabitEthernet0/2/0

 undo shutdown

 ip address 172.16.2.2 255.255.255.0

 mpls

 mpls ldp

interface gigabitethernet0/1/0

 undo shutdown

 ip binding vpn-instance vpna

 ip address 10.2.1.2 255.255.255.0

interface LoopBack1

 ip address 3.3.3.3 255.255.255.255

bgp 100

 peer 1.1.1.1 as-number 100

 peer 1.1.1.1 connect-interface LoopBack1

 ipv4-family unicast

  undo synchronization

  peer 1.1.1.1 enable

 ipv4-family vpnv4

  policy vpn-target

  peer 1.1.1.1 enable

 ipv4-family vpn-instance vpna

  peer 10.2.1.1 as-number 65420

  import-route direct

ospf 100

 area 0.0.0.0

  network 3.3.3.3 0.0.0.0

  network 172.16.2.0 0.0.0.255

bfd 2to1_vpn bind peer-ip 10.1.1.2 vpn-instance vpna

 discriminator local 21

 discriminator remote 12

return

P configuration file

sysname P

 mpls lsr-id 2.2.2.2

 mpls

mpls ldp

interface GigabitEthernet0/1/0

 undo shutdown

 ip address 172.16.1.2 255.255.255.0

 mpls

 mpls ldp

interface GigabitEthernet0/2/0

 undo shutdown

 ip address 172.16.2.1 255.255.255.0

 mpls

 mpls ldp

interface LoopBack1

  ip address 2.2.2.2 255.255.255.255

ospf 100

 area 0.0.0.0

  network 172.16.1.0 0.0.0.255

  network 172.16.2.0 0.0.0.255

  network 2.2.2.2 0.0.0.0

return

CE1 configuration file

 sysname CE1

interface gigabitethernet0/1/0

 undo shutdown

ip address 10.1.1.1 255.255.255.0

bgp 65410

 peer 10.1.1.2 as-number 100

 ipv4-family unicast

  import-route direct

  peer 10.1.1.2 enable

return

CE2 configuration file

 sysname CE2

interface gigabitethernet0/1/0

 undo shutdown

 ip address 10.2.1.1 255.255.255.0

bgp 65420

 peer 10.2.1.2 as-number 100

 ipv4-family unicast

  import-route direct

  peer 10.2.1.2 enable

return

Example for Configuring BFD for Static VPN Routes

In CE dual-homing networking, after a static route on a CE is bound to a BFD session, the static route can detect link faults or refresh itself based on the BFD session status. This implementation ensures quick VPN traffic convergence.

Networking Requirements

On the network shown in Figure 3-7, CE1 and CE2 belong to VPN A. Two default routes with the next hops as PE1 and PE2 respectively are configured on CE1. The two routes work in load-balancing mode. The static routes bound to VPN A are configured on PE1 and PE2 separately and are imported to BGP.

BFD sessions are established between PE1 and CE1, and between PE2 and CE1. It is required that BFD be configured on PE1 and PE2 to detect the link faults of static VPN routes. In normal situations, the traffic from CE1 to the public network can be forwarded through PE1 and PE2 in load balancing mode. If the link between CE1 and PE1 or PE2 fails, CE1 detects the link fault by tracking BFD session status and updates the route. Then, CE1 switches traffic to the other link for transmission.

Figure 3-7 Configuring BFD for static VPN routes

Interfaces 1 through 3 in this example represent GE 0/1/0, GE 0/2/0, and GE 0/3/0, respectively.

Configuration Notes

When configuring BFD for static VPN routes, ensure that the CE is dual-homed to two PEs configured with VPN instances of different RDs.

Configuration Roadmap

The configuration roadmap is as follows:

Configure OSPF for PEs on the MPLS backbone network to communicate.
Establish MPLS LSPs between PEs.
Configure VPN instances on PEs and bind each interface that connects a PE to a CE to the VPN instance on that PE.
Configure MP-IBGP on the PEs to exchange VPN routing information.
Configure two default routes with the next hops as PE1 and PE2 respectively on CE1 to implement load balancing between PE1 and PE2.
Configure a static route bound to VPN A on PE1 and PE2 and import the static route into BGP.
Configure an MP-EBGP peer relationship between PE3 and CE2.
Configure static BFD sessions with automatically negotiated discriminators between PE1 and CE1, and between PE2 and CE1.
Configure BFD for VPN static routes on PE1 and PE2.

Data Preparation

To complete the configuration, you need the following data:

MPLS LSR IDs of the PEs
Names, RDs, and VPN targets of the VPN instances on the PEs
Local and peer IP addresses of the BFD session

Procedure

Configure an IGP for PEs on the MPLS backbone network to communicate. This example uses OSPF as the IGP.

# Configure PE1.

<HUAWEI> system-view
[~HUAWEI] sysname PE1
[*HUAWEI] commit
[~PE1] interface loopback 1
[*PE1-LoopBack1] ip address 2.2.2.2 32
[*PE1-LoopBack1] commit
[*PE1-LoopBack1] quit
[*PE1] interface gigabitethernet 0/1/0
[*PE1-GigabitEthernet0/1/0] ip address 11.11.11.1 24
[*PE1-GigabitEthernet0/1/0] commit
[*PE1-GigabitEthernet0/1/0] quit
[*PE1] interface gigabitethernet 0/2/0
[*PE1-GigabitEthernet0/2/0] ip address 33.33.33.1 24
[*PE1-GigabitEthernet0/2/0] commit
[*PE1-GigabitEthernet0/2/0] quit
[*PE1] ospf
[*PE1-ospf-1] area 0
[*PE1-ospf-1-area-0.0.0.0] network 11.11.11.0 0.0.0.255
[*PE1-ospf-1-area-0.0.0.0] network 33.33.33.0 0.0.0.255
[*PE1-ospf-1-area-0.0.0.0] network 2.2.2.2 0.0.0.0
[*PE1-ospf-1-area-0.0.0.0] commit
[~PE1-ospf-1-area-0.0.0.0] quit
[~PE1-ospf-1] quit

Configure PE2.

<HUAWEI> system-view
[~HUAWEI] sysname PE2
[*HUAWEI] commit
[~PE2] interface loopback 1
[*PE2-LoopBack1] ip address 3.3.3.3 32
[*PE2-LoopBack1] commit
[*PE2-LoopBack1] quit
[*PE2] interface gigabitethernet 0/1/0
[*PE2-GigabitEthernet0/1/0] ip address 22.22.22.1 24
[*PE2-GigabitEthernet0/1/0] commit
[*PE2-GigabitEthernet0/1/0] quit
[*PE2] interface gigabitethernet 0/2/0 
[*PE2-GigabitEthernet0/2/0] ip address 33.33.33.2 24
[*PE2-GigabitEthernet0/2/0] commit
[*PE2-GigabitEthernet0/2/0] quit
[*PE2] ospf
[*PE2-ospf-1] area 0
[*PE2-ospf-1-area-0.0.0.0] network 22.22.22.0 0.0.0.255
[*PE2-ospf-1-area-0.0.0.0] network 33.33.33.0 0.0.0.255
[*PE2-ospf-1-area-0.0.0.0] network 3.3.3.3 0.0.0.0
[*PE2-ospf-1-area-0.0.0.0] commit
[~PE2-ospf-1-area-0.0.0.0] quit
[~PE2-ospf-1] quit

Configure PE3.

<HUAWEI> system-view
[~HUAWEI] sysname PE3
[*HUAWEI] commit
[~PE3] interface loopback 1
[*PE3-LoopBack1] ip address 4.4.4.4 32
[*PE3-LoopBack1] [*PE3-LoopBack1] quit
[*PE3-LoopBack1] [*PE3-LoopBack1] quit
[*PE3-LoopBack1] quit
[*PE3] interface gigabitethernet 0/1/0
[*PE3-GigabitEthernet0/1/0] ip address 11.11.11.2 24
[*PE3-GigabitEthernet0/1/0] commit
[*PE3-GigabitEthernet0/1/0] quit
[*PE3] interface gigabitethernet 0/2/0
[*PE3-GigabitEthernet0/2/0] ip address 22.22.22.2 24
[*PE3-GigabitEthernet0/2/0] commit
[*PE3-GigabitEthernet0/2/0] quit
[*PE3] ospf
[*PE3-ospf-1] area 0
[*PE3-ospf-1-area-0.0.0.0] network 11.11.11.0 0.0.0.255
[*PE3-ospf-1-area-0.0.0.0] network 22.22.22.0 0.0.0.255
[*PE3-ospf-1-area-0.0.0.0] network 4.4.4.4 0.0.0.0
[*PE3-ospf-1-area-0.0.0.0] commit
[~PE3-ospf-1-area-0.0.0.0] quit
[~PE3-ospf-1] quit

After the configurations are complete, OSPF neighbor relationships can be set up between PE1, PE2, and PE3. Run the display ip routing-table command. The command output shows that the PEs have learned the routes to each other's Loopback 1 interface.

The following example uses the command output on PE1.

<PE1> display ip routing-table

<keyword conref="../commonterms/commonterms.xml#commonterms/route-flags"></keyword>
------------------------------------------------------------------------------
Routing Tables: _public_
         Destinations : 14       Routes : 15

Destination/Mask    Proto  Pre  Cost     Flags NextHop         Interface

        2.2.2.2/32  Direct 0    0           D  127.0.0.1       LoopBack1
        3.3.3.3/32  OSPF   10   2           D  33.33.33.2       GigabitEthernet0/2/0
        4.4.4.4/32  OSPF   10   2           D  11.11.11.2       GigabitEthernet0/1/0
      11.11.11.0/24  Direct 0    0           D  11.11.11.1       GigabitEthernet0/1/0
      11.11.11.2/32  Direct 0    0           D  127.0.0.1       GigabitEthernet0/1/0
    11.11.11.255/32  Direct 0    0           D  127.0.0.1       GigabitEthernet0/1/0
      22.22.22.0/24  OSPF   10    2          D  11.11.11.2       GigabitEthernet0/1/0
                    OSPF   10    2          D  33.33.33.2       GigabitEthernet0/2/0
      33.33.33.0/24  Direct 0    0           D  33.33.33.1       GigabitEthernet0/2/0
      33.33.33.1/32  Direct 0    0           D  127.0.0.1       GigabitEthernet0/2/0
    33.33.33.255/32  Direct 0    0           D  127.0.0.1       GigabitEthernet0/2/0
      127.0.0.0/8   Direct 0    0           D  127.0.0.1       InLoopBack0
      127.0.0.1/32  Direct 0    0           D  127.0.0.1       InLoopBack0
127.255.255.255/32  Direct 0    0           D  127.0.0.1       InLoopBack0
255.255.255.255/32  Direct 0    0           D  127.0.0.1       InLoopBack0

Configure MPLS and MPLS LDP both globally and per interface on each node of the backbone network and set up LDP LSPs.

# Configure PE1.

[~PE1] mpls lsr-id 2.2.2.2
[*PE1] mpls
[*PE1-mpls] quit
[*PE1] mpls ldp
[*PE1-mpls-ldp] quit
[*PE1] interface gigabitethernet 0/1/0
[*PE1-GigabitEthernet0/1/0] mpls
[*PE1-GigabitEthernet0/1/0] mpls ldp
[*PE1-GigabitEthernet0/1/0] commit
[*PE1-GigabitEthernet0/1/0] quit
[*PE1] interface gigabitethernet 0/2/0
[*PE1-GigabitEthernet0/2/0] mpls 
[*PE1-GigabitEthernet0/2/0] mpls ldp
[*PE1-GigabitEthernet0/2/0] commit
[~PE1-GigabitEthernet0/2/0] quit

# Configure PE2.

[~PE2] mpls lsr-id 3.3.3.3
[*PE2] mpls
[*PE2-mpls] quit
[*PE2] mpls ldp
[*PE2-mpls-ldp] quit
[*PE2] interface gigabitethernet 0/1/0
[*PE2-GigabitEthernet0/1/0] mpls
[*PE2-GigabitEthernet0/1/0] mpls ldp
[*PE2-GigabitEthernet0/1/0] commit
[*PE2-GigabitEthernet0/1/0] quit
[*PE2] interface gigabitethernet 0/2/0
[*PE2-GigabitEthernet0/2/0] mpls
[*PE2-GigabitEthernet0/2/0] mpls ldp
[*PE2-GigabitEthernet0/2/0] commit
[~PE2-GigabitEthernet0/2/0] quit

Configure PE3.

[~PE3] mpls lsr-id 4.4.4.4
[*PE3] mpls
[*PE3-mpls] quit
[*PE3] mpls ldp
[*PE3-mpls-ldp] quit
[*PE3] interface gigabitethernet 0/1/0
[*PE3-GigabitEthernet0/1/0] mpls
[*PE3-GigabitEthernet0/1/0] mpls ldp
[*PE3-GigabitEthernet0/1/0] commit
[*PE3-GigabitEthernet0/1/0] quit
[*PE3] interfacegigabitethernet 0/2/0
[*PE3-GigabitEthernet0/2/0] mpls
[*PE3-GigabitEthernet0/2/0] mpls ldp
[*PE3-GigabitEthernet0/2/0] commit
[~PE3-GigabitEthernet0/2/0] quit

After the configurations are complete, LDP sessions can be set up between PEs. Run the display mpls ldp session command. The command output shows that the Status field is Operational.

The following example uses the command output on PE1.

<PE1> display mpls ldp session

               LDP Session(s) in Public Network
 Codes: LAM(Label Advertisement Mode), SsnAge Unit(DDD:HH:MM)
 An asterisk (*) before a session means the session is being deleted.

 ------------------------------------------------------------------------------
 Peer-ID            Status      LAM  SsnRole  SsnAge      KA-Sent/Rcv
 ------------------------------------------------------------------------------
 3.3.3.3:0          Operational DU   Passive  000:02:22   572/572
 4.4.4.4:0          Operational DU   Passive  000:02:21   566/566
 ------------------------------------------------------------------------------
 TOTAL: 2 session(s) Found.
 LAM : Label Advertisement Mode      SsnAge Unit : DDD:HH:MM

Configure VPN instances on PEs and bind each interface that connects a PE to a CE to the VPN instance on that PE.

# Configure PE1.

[~PE1] ip vpn-instance VPNA
[*PE1-vpn-instance-VPNA] ipv4-family
[*PE1-vpn-instance-VPNA-af-ipv4] route-distinguisher 100:1
[*PE1-vpn-instance-VPNA-af-ipv4] vpn-target 111:1 both
[*PE1-vpn-instance-VPNA-af-ipv4] quit
[*PE1-vpn-instance-VPNA] quit
[*PE1] interface gigabitethernet 0/3/0
[*PE1-GigabitEthernet0/3/0] ip binding vpn-instance VPNA
[*PE1-GigabitEthernet0/3/0] ip address 10.1.1.2 24
[*PE1-GigabitEthernet0/3/0] commit
[~PE1-GigabitEthernet0/3/0] quit

# Configure PE2.

[~PE2] ip vpn-instance VPNA
[*PE2-vpn-instance-VPNA] ipv4-family
[*PE2-vpn-instance-VPNA-af-ipv4] route-distinguisher 100:2
[*PE2-vpn-instance-VPNA-af-ipv4] vpn-target 111:1 both
[*PE2-vpn-instance-VPNA-af-ipv4] quit
[*PE2-vpn-instance-VPNA] quit
[*PE2] interface gigabitethernet 0/3/0
[*PE2-GigabitEthernet0/3/0] ip binding vpn-instance VPNA
[*PE2-GigabitEthernet0/3/0] ip address 10.2.1.2 24
[*PE2-GigabitEthernet0/3/0] commit
[~PE2-GigabitEthernet0/3/0] quit

# Configure PE3.

[~PE3] ip vpn-instance VPNA
[*PE3-vpn-instance-VPNA] ipv4-family
[*PE3-vpn-instance-VPNA-af-ipv4] route-distinguisher 100:3
[*PE3-vpn-instance-VPNA-af-ipv4] vpn-target 111:1 both
[*PE3-vpn-instance-VPNA-af-ipv4] quit
[*PE3-vpn-instance-VPNA] quit
[*PE3] interface gigabitethernet 0/3/0
[*PE3-GigabitEthernet0/3/0] ip binding vpn-instance VPNA
[*PE3-GigabitEthernet0/3/0] ip address 10.3.1.1 24
[*PE3-GigabitEthernet0/3/0] commit
[~PE3-GigabitEthernet0/3/0] quit

Configure CE1.

[~CE1] interface gigabitethernet 0/1/0
[~CE1-GigabitEthernet0/1/0] ip address 10.1.1.1 24
[*CE1-GigabitEthernet0/1/0] commit
[*CE1-GigabitEthernet0/1/0] quit 
[*CE1] interface gigabitethernet 0/2/0
[*CE1-GigabitEthernet0/2/0] ip address 10.2.1.1 24
[*CE1-GigabitEthernet0/2/0] commit
[~CE1-GigabitEthernet0/2/0] quit

# Configure CE2.

[*CE2] interface gigabitethernet 0/1/0
[*CE2-GigabitEthernet0/1/0] ip address 10.3.1.2 24
[*CE2-GigabitEthernet0/1/0] commit
[~CE2-GigabitEthernet0/1/0] quit

After completing the configurations, run the display ip vpn-instance verbose command on PEs to view the configurations of VPN instances. Each PE can ping its connected CE.

The following example uses the command output on PE1.

<PE1> display ip vpn-instance verbose
 Total VPN-Instances configured : 1
 Total IPv4 VPN-Instances configured : 1 
 Total IPv6 VPN-Instances configured : 0
 VPN-Instance Name and ID : VPNA, 1
  Interfaces : GigabitEthernet0/3/0
 Address family ipv4
  Create date : 2008/09/21 12:18:46
  Up time : 0 days, 02 hours, 35 minutes and 58 seconds
  Vrf Status : UP
  Route Distinguisher : 100:1
  Export VPN Targets :  111:1
  Import VPN Targets :  111:1
  Label policy : label per route
  The diffserv-mode Information is : uniform
  The ttl-mode Information is : pipe

[*PE1] ping -vpn-instance VPNA 10.1.1.1
PING 10.1.1.1: 56  data bytes, press CTRL_C to break
    Reply from 10.1.1.1: bytes=56 Sequence=1 ttl=255 time=130 ms
    Reply from 10.1.1.1: bytes=56 Sequence=2 ttl=255 time=60 ms
    Reply from 10.1.1.1: bytes=56 Sequence=3 ttl=255 time=40 ms
    Reply from 10.1.1.1: bytes=56 Sequence=4 ttl=255 time=30 ms
    Reply from 10.1.1.1: bytes=56 Sequence=5 ttl=255 time=30 ms

  --- 10.1.1.1 ping statistics ---
    5 packet(s) transmitted
    5 packet(s) received
    0.00% packet loss
round-trip min/avg/max = 30/58/130 ms

Import the VPN routes between PE1, PE2, and CE1.

Configure two default routes with the next hops as PE1 and PE2 respectively on CE1 to implement load balancing between PE1 and PE2. Configure the static routes to be bound to the VPN instances on PE1 and PE2 and import the static routes into BGP.

# Configure CE1.

[~CE1] load-balance packet all
[*CE1] ip route-static 0.0.0.0 0 10.1.1.2 
[*CE1] ip route-static 0.0.0.0 0 10.2.1.2
[*CE1] commit

# Configure PE1.

[~PE1] ip route-static vpn-instance VPNA 1.1.1.1 32 10.1.1.1
[*PE1] bgp 100
[*PE1-bgp] ipv4-family vpn-instance VPNA
[*PE1-bgp-VPNA] import-route direct
[*PE1-bgp-VPNA] import-route static
[*PE1-bgp-VPNA] commit
[~PE1-bgp-VPNA] quit

# Configure PE2.

[~PE2] ip route-static vpn-instance VPNA 1.1.1.1 32 10.2.1.1
[*PE2] bgp 100
[*PE2-bgp] ipv4-family vpn-instance VPNA
[*PE2-bgp-VPNA] import-route direct
[*PE2-bgp-VPNA] import-route static
[*PE2-bgp-VPNA] commit
[~PE2-bgp-VPNA] quit

Set up an EBGP peer relationship between PE3 and CE2, and import VPN routes to EBGP.

# Configure CE2.

[~CE2] bgp 65410
[*CE2-bgp] peer 10.3.1.1 as-number 100
[*CE2-bgp] import-route direct
[*CE2-bgp] commit
[~CE2] quit

# Configure PE3 and specify the number of routes carrying out load balancing to 2 on PE3.

[~PE3] bgp 100
[*PE3-bgp] ipv4-family vpn-instance VPNA
[*PE3-bgp-VPNA] peer 10.3.1.2 as-number 65410
[*PE3-bgp-VPNA] import-route direct
[*PE3-bgp-VPNA] maximum load-balancing 2
[*PE3-bgp-VPNA] commit
[~PE3-bgp-VPNA] quit

Set up an MP-IBGP peer relationship between PEs.

# Configure PE1.

[~PE1] bgp 100
[~PE1-bgp] peer 3.3.3.3 as-number 100
[*PE1-bgp] peer 3.3.3.3 connect-interface loopback 1
[*PE1-bgp] peer 4.4.4.4 as-number 100
[*PE1-bgp] peer 4.4.4.4 connect-interface loopback 1
[*PE1-bgp] ipv4-family vpnv4
[*PE1-bgp-af-vpnv4] peer 3.3.3.3 enable
[*PE1-bgp-af-vpnv4] peer 4.4.4.4 enable
[*PE1-bgp-af-vpnv4] commit
[~PE1-bgp-af-vpnv4] quit
[~PE1-bgp] quit

# Configure PE2.

[*PE2] bgp 100
[*PE2-bgp] peer 2.2.2.2 as-number 100
[*PE2-bgp] peer 2.2.2.2 connect-interface loopback 1
[*PE2-bgp] peer 4.4.4.4 as-number 100
[*PE2-bgp] peer 4.4.4.4 connect-interface loopback 1
[*PE2-bgp] ipv4-family vpnv4
[*PE2-bgp-af-vpnv4] peer 2.2.2.2 enable
[*PE2-bgp-af-vpnv4] peer 4.4.4.4 enable
[*PE2-bgp-af-vpnv4] commit
[~PE2-bgp-af-vpnv4] quit
[~PE2-bgp] quit

# Configure PE3.

[~PE3] bgp 100
[*PE3-bgp] peer 2.2.2.2 as-number 100
[*PE3-bgp] peer 2.2.2.2 connect-interface loopback 1
[*PE3-bgp] peer 3.3.3.3 as-number 100
[*PE3-bgp] peer 3.3.3.3 connect-interface loopback 1
[*PE3-bgp] ipv4-family vpnv4
[*PE3-bgp-af-vpnv4] peer 2.2.2.2 enable
[*PE3-bgp-af-vpnv4] peer 3.3.3.3 enable
[*PE3-bgp-af-vpnv4] commit
[~PE3-bgp-af-vpnv4] quit
[~PE3-bgp] quit

After completing the configurations, run the display bgp vpnv4 all peer command on PEs. The command output shows that BGP peer relationships have been established between PEs.

<PE1> display bgp vpnv4 all peer

 BGP local router ID : 2.2.2.2
 Local AS number : 100
 Total number of peers : 2                 Peers in established state : 2

Peer            V    AS  MsgRcvd  MsgSent    OutQ  Up/Down  State PrefRcv

4.4.4.4         4   100      205      202       0 03:05:25 Established       0
3.3.3.3         4   100      197      254       0 03:06:54 Established       0

Configure BFD sessions with automatically negotiated discriminators.

Set up BFD sessions between CE1 and PE1, and between CE1 and PE2.

# Configure PE1.

[~PE1] bfd
[*PE1-bfd] quit
[*PE1] bfd pe1_to_ce1 bind peer-ip 10.1.1.1 vpn-instance VPNA interface gigabitethernet 0/3/0 source-ip 10.1.1.2 auto
[*PE1-bfd-session-pe1_to_ce1] commit
[~PE1-bfd-session-pe1_to_ce1] quit

# Configure PE2.

[~PE2] bfd
[*PE2-bfd] quit
[*PE2] bfd pe2_to_ce1 bind peer-ip 10.2.1.1 vpn-instance VPNA interface gigabitethernet 0/3/0 source-ip 10.2.1.2 auto
[*PE2-bfd-session-pe2_to_ce1] commit
[~PE2-bfd-session-pe2_to_ce1] quit

# Configure CE1.

[~CE1] bfd
[*CE1-bfd] quit
[*CE1] bfd ce1_to_pe1 bind peer-ip 10.1.1.2 interface gigabitethernet 0/1/0 source-ip 10.1.1.1 auto
[*CE1-bfd-session-ce1_to_pe1] commit
[*CE1-bfd-session-ce1_to_pe1] quit
[*CE1] bfd ce1_to_pe2 bind peer-ip 10.2.1.2 interface gigabitethernet 0/2/0 source -ip 10.2.1.1 auto
[*CE1-bfd-session-ce1_to_pe2] commit
[~CE1-bfd-session-ce1_to_pe2] quit

After completing the configurations, run the display bfd session all verbose command on each PE and CE. The command output shows that a one-hop static auto-negotiation BFD session is established, and the session status is Up. The local and remote IDs of the BFD session are obtained through auto-negotiation. Use PE1 and CE1 as an example.

The following example uses the command output on PE1 and CE1.

<PE1> display bfd session all verbose

(w): State in WTR 
(*): State is invalid
--------------------------------------------------------------------------------
  (One Hop) State : Up                      Name : pe1_to_ce1
------------------------------------------------------------------------------
  Local Discriminator    : 8192             Remote Discriminator   : 8192
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(GigabitEthernet0/3/0)
  Bind Session Type      : Static_Auto
  Bind Peer IP Address   : 10.1.1.1
  Bind Interface         : GigabitEthernet0/3/0
  FSM Board Id           : 3                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): -                Actual Rx Interval (ms): -
  Local Detect Multi     : 3                Detect Interval (ms)   : -
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 254  
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : -                Config PST             : Enable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : AUTO
  Session TX TmrID       : -                Session Detect TmrID   : -
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Not Up Reason  : In negotiation 
  Session Description    : - 
------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 1/0

<CE1> display bfd session all verbose

(w): State in WTR 
(*): State is invalid
--------------------------------------------------------------------------------
  (One Hop) State : Up                      Name : ce1_to_pe1
--------------------------------------------------------------------------------
  Local Discriminator    : 8192             Remote Discriminator   : 8192
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(GigabitEthernet0/1/0)
  Bind Session Type      : Static_Auto
  Bind Peer IP Address   : 10.1.1.2
  Bind Interface         : GigabitEthernet0/1/0
  FSM Board Id           : 3                TOS-EXP                : 6
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): -                Actual Rx Interval (ms): -
  Local Detect Multi     : 3                Detect Interval (ms)   : -
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : -                Config PST             : Enable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : AUTO
  Session TX TmrID       : -                Session Detect TmrID   : -
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  PDT Index              : FSM-5020000 | RCV-0 | IF-5020000 | TOKEN-0
  Session Description    : -
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
  (One Hop) State : Up                         Name : ce1_to_pe2
--------------------------------------------------------------------------------
  Local Discriminator    : 8193             Remote Discriminator   : 8193
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(GigabitEthernet0/2/0)
  Bind Session Type      : Static_Auto
  Bind Peer IP Address   : 10.2.1.2
  Bind Interface         : GigabitEthernet0/2/0
  FSM Board Id           : 3                TOS-EXP                : 6
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): -                Actual Rx Interval (ms): -
  Local Detect Multi     : 3                Detect Interval (ms)   : -
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : -                Config PST             : Enable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : AUTO
  Session TX TmrID       : -                Session Detect TmrID   : -
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  PDT Index              : FSM-5020000 | RCV-0 | IF-5020000 | TOKEN-0
  Session Description    : -
--------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 2/0

Configure BFD for VPN static routes on the PEs.

# Configure PE1.

[~PE1] ip route-static vpn-instance VPNA 1.1.1.1 255.255.255.255 10.1.1.1 track bfd-session pe1_to_ce1

[*PE1] commit

# Configure PE2.

[~PE2] ip route-static vpn-instance VPNA 1.1.1.1 255.255.255.255 10.2.1.1 track bfd-session pe2_to_ce1

[*PE2] commit

Verify the configuration.

# After completing the configurations, run the display ip routing-table command on PE1 to check the VPN routing table information on PE1. The command output shows that a static route exists in the routing table.

<PE1> display ip routing-table vpn-instance VPNA
Route Flags: R - relay, D - download to fib, T - to vpn-instance, B - black hole route
------------------------------------------------------------------------------
Routing Tables: VPNA
         Destinations : 7        Routes : 7

Destination/Mask    Proto  Pre  Cost     Flags NextHop         Interface

        1.1.1.1/32 Static 60  0         RD 10.1.1.1       GigabitEthernet0/3/0
       10.1.1.0/24  Direct 0    0           D  10.1.1.2        GigabitEthernet0/3/0
       10.1.1.2/32  Direct 0    0           D  127.0.0.1       GigabitEthernet0/3/0
     10.1.1.255/32  Direct 0    0           D  127.0.0.1       GigabitEthernet0/3/0
       10.2.1.0/24  IBGP   255  0          RD  3.3.3.3         GigabitEthernet0/2/0
       10.3.1.0/24  IBGP   255  0          RD  4.4.4.4         GigabitEthernet0/1/0
255.255.255.255/32  Direct 0    0           D  127.0.0.1       InLoopBack0

# On CE1, run the tracert command to ping the gateway through which the packets destined for CE2 pass. The command output shows that load balancing is implemented between PE1 and PE2 at the first hop.

<CE1> tracert 10.3.1.2
 traceroute to  10.3.1.2(10.3.1.2), max hops: 30 ,packet length: 40
 1 10.1.1.2 20 ms 10.2.1.2 1 ms 10.1.1.2 40 ms
 2 10.3.1.1 40 ms  30 ms  50 ms
 3 10.3.1.2 80 ms  80 ms  60 ms

# Run the display ip routing-table command on PE3 to check the routing table information on PE3. The command output shows that there are two routes to PE1 (1.1.1.1), with the next hops being 3.3.3.3 and 2.2.2.2 respectively. The two routes work in load-balancing mode.

<PE3> display ip routing-table vpn-instance VPNA
Route Flags: R - relay, D - download to fib, T - to vpn-instance, B - black hole route
------------------------------------------------------------------------------
Routing Tables: VPNA
         Destinations : 7        Routes : 8

Destination/Mask    Proto  Pre  Cost     Flags NextHop         Interface

        1.1.1.1/32  IBGP   255  0          RD  3.3.3.3         GigabitEthernet0/2/0
                    IBGP   255  0          RD  2.2.2.2         GigabitEthernet0/1/0
       10.1.1.0/24  IBGP   255  0          RD  2.2.2.2         GigabitEthernet0/1/0
       10.2.1.0/24  IBGP   255  0          RD  3.3.3.3         GigabitEthernet0/2/0
       10.3.1.0/24  Direct 0    0           D  10.3.1.1        GigabitEthernet0/3/0
       10.3.1.1/32  Direct 0    0           D  127.0.0.1       GigabitEthernet0/3/0
     10.3.1.255/32  Direct 0    0           D  127.0.0.1       GigabitEthernet0/3/0
255.255.255.255/32  Direct 0    0           D  127.0.0.1       InLoopBack0

# Run the tracert command on CE2 to check the traffic destined for CE1. The command output shows that load balancing is performed when the traffic leaves PE3.

[~CE2] tracert 1.1.1.1
 traceroute to  1.1.1.1(1.1.1.1), max hops: 30 ,packet length: 40
 1 10.3.1.1 9 ms  2 ms  2 ms
 2 10.2.1.2 < AS=100 > 6 ms  5 ms  2 ms
 3 10.2.1.1 < AS=100 > 6 ms  6 ms  5 ms

# Run the shutdown command on GE 0/1/0 of CE1 to simulate a link fault.

[~CE1-GigabitEthernet0/1/0] shutdown

# Run the display bfd session all verbose command on PE1. The command output shows that the status of the BFD session is Down.

<PE1> display bfd session all verbose

(w): State in WTR 
(*): State is invalid
--------------------------------------------------------------------------------
  (One Hop) State : Down                   Name : pe1_to_ce1
------------------------------------------------------------------------------
  Local Discriminator    : 8192             Remote Discriminator   : 8192
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(GigabitEthernet0/3/0)
  Bind Session Type      : Static_Auto
  Bind Peer IP Address   : 10.1.1.1
  Bind Interface         : GigabitEthernet0/3/0
  FSM Board Id           : 3                TOS-EXP                : 6
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): -                Actual Rx Interval (ms): -
  Local Detect Multi     : 3                Detect Interval (ms)   : -
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255  
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : -                Config PST             : Enable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : AUTO
  Session TX TmrID       : -                Session Detect TmrID   : -
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Not Up Reason  : In negotiation 
  Session Description    : - 
------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 1/0

# Run the display ip routing-table vpn-instance command on PE1 to check the VPN routing table. The command output shows that the next hop of the route destined for CE1 is only PE2.

<PE1> display ip routing-table vpn-instance VPNA
Route Flags: R - relay, D - download to fib, T - to vpn-instance, B - black hole route
------------------------------------------------------------------------------
Routing Tables: VPNA
         Destinations : 4        Routes : 4

Destination/Mask    Proto  Pre  Cost     Flags NextHop         Interface

    1.1.1.1/32  EBGP   255  0           RD  3.3.3.3         GigabitEthernet0/2/0
       10.2.1.0/24  IBGP   255  0          RD  3.3.3.3         GigabitEthernet0/2/0
       10.3.1.0/24  IBGP   255  0          RD  4.4.4.4         GigabitEthernet0/1/0
255.255.255.255/32  Direct 0    0           D  127.0.0.1       InLoopBack0

# On CE1, check the gateway through which the packets destined for CE2 pass. The command output shows that load balancing is not carried out between PE1 and PE2 at the first hop, and the traffic flows only through PE2.

<CE3> tracert 10.3.1.2
 traceroute to  10.3.1.2(10.3.1.2), max hops: 30 ,packet length: 40
 1 10.2.1.2 50 ms  30 ms  10 ms
 2 10.3.1.1 110 ms  70 ms  90 ms
 3 10.3.1.2 60 ms  70 ms  80 ms

# Run the display ip routing-table vpn-instance command on PE3 to check the routing table. The command output shows that there is only one route to CE1 (1.1.1.1) with the next hop as PE1 (3.3.3.3).

<PE3> display ip routing-table vpn-instance VPNA
Route Flags: R - relay, D - download to fib, T - to vpn-instance, B - black hole route
------------------------------------------------------------------------------
Routing Tables: VPNA
         Destinations : 6        Routes : 6

Destination/Mask    Proto  Pre  Cost     Flags NextHop         Interface

        1.1.1.1/32  IBGP   255  0          RD  3.3.3.3         GigabitEthernet0/2/0
       10.2.1.0/24  IBGP   255  0          RD  3.3.3.3         GigabitEthernet0/2/0
       10.3.1.0/24  Direct 0    0           D  10.3.1.1        GigabitEthernet0/3/0
       10.3.1.1/32  Direct 0    0           D  127.0.0.1       GigabitEthernet0/3/0
     10.3.1.255/32  Direct 0    0           D  127.0.0.1       GigabitEthernet0/3/0
255.255.255.255/32  Direct 0    0           D  127.0.0.1       InLoopBack0

# On CE2, check the traffic destined for CE1. The command output shows that the traffic is forwarded through GE 0/2/0 (10.2.1.2) after the traffic leaves PE3.

[~CE2] tracert 1.1.1.1
 traceroute to  1.1.1.1(1.1.1.1), max hops: 30 ,packet length: 40
 1 10.3.1.1 9 ms  2 ms  2 ms
 2 10.2.1.2 < AS=100 > 6 ms  5 ms  5 ms
 3 10.2.1.1 < AS=100 > 6 ms  5 ms  5 ms

Use a tester to generate traffic, and the traffic is forwarded in load balancing mode. After a link between CE1 and PE1 or a link between CE1 and PE2 fails, you can find that the traffic is switched in less than 50 ms.

Configuration Files

PE1 configuration file

#
 sysname PE1
#
ip vpn-instance VPNA
 ipv4-family
  route-distinguisher 100:1
  apply-label per-instance
  vpn-target 111:1 export-extcommunity
  vpn-target 111:1 import-extcommunity
#
bfd
#
mpls lsr-id 2.2.2.2
#
mpls
#
mpls ldp
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 11.11.11.1 255.255.255.0
 mpls
 mpls ldp
#
interface GigabitEthernet0/2/0
 undo shutdown
 ip address 33.33.33.1 255.255.255.0
 mpls
 mpls ldp
#
interface GigabitEthernet0/3/0
 undo shutdown
 ip binding vpn-instance VPNA
 ip address 10.1.1.2 255.255.255.0
#
interface LoopBack1
 ip address 2.2.2.2 255.255.255.255
#
bgp 100
 peer 3.3.3.3 as-number 100
 peer 3.3.3.3 connect-interface LoopBack1
 peer 4.4.4.4 as-number 100
 peer 4.4.4.4 connect-interface LoopBack1
 #
 ipv4-family unicast
  undo synchronization
  peer 3.3.3.3 enable
  peer 4.4.4.4 enable
 #
 ipv4-family vpnv4
  policy vpn-target
  peer 3.3.3.3 enable
  peer 4.4.4.4 enable
 #
 ipv4-family vpn-instance VPNA
  import-route direct
  import-route static
#
ospf 1
 area 0.0.0.0
  network 11.11.11.0 0.0.0.255
  network 33.33.33.0 0.0.0.255
  network 2.2.2.2 0.0.0.0
#
ip route-static vpn-instance VPNA 1.1.1.1 255.255.255.255 10.1.1.1 track bfd-session pe1_to_ce1
#
bfd pe1_to_ce1 bind peer-ip 10.1.1.1 vpn-instance VPNA interface GigabitEthernet0/3/0 source-ip 10.1.1.2 auto
#
return

PE2 configuration file

#
 sysname PE2
#
ip vpn-instance VPNA
 ipv4-family
  route-distinguisher 100:2
  apply-label per-instance
  vpn-target 111:1 export-extcommunity
  vpn-target 111:1 import-extcommunity
#
 bfd
#
mpls lsr-id 3.3.3.3
#
mpls
#
mpls ldp
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 22.22.22.1 255.255.255.0
 mpls
 mpls ldp
#
interface GigabitEthernet0/2/0
 undo shutdown
 ip address 33.33.33.2 255.255.255.0
 mpls
 mpls ldp
#
interface GigabitEthernet0/3/0
 undo shutdown
 ip binding vpn-instance VPNA
 ip address 10.2.1.2 255.255.255.0
#
interface LoopBack1
 ip address 3.3.3.3 255.255.255.255
#
bgp 100
 peer 2.2.2.2 as-number 100
 peer 2.2.2.2 connect-interface LoopBack1
 peer 4.4.4.4 as-number 100
 peer 4.4.4.4 connect-interface LoopBack1
 #
 ipv4-family unicast
  undo synchronization
  peer 2.2.2.2 enable
  peer 4.4.4.4 enable
 #
 ipv4-family vpnv4
  policy vpn-target
  peer 2.2.2.2 enable
  peer 4.4.4.4 enable
 #
 ipv4-family vpn-instance VPNA
  import-route direct
  import-route static
#
ospf 1
 area 0.0.0.0
  network 33.33.33.0 0.0.0.255
  network 22.22.22.0 0.0.0.255
  network 3.3.3.3 0.0.0.0
#
 ip route-static vpn-instance VPNA 1.1.1.1 255.255.255.255 10.2.1.1 track bfd-session pe2_to_ce1
#
bfd pe2_to_ce1 bind peer-ip 10.2.1.1 vpn-instance VPNA interface GigabitEthernet0/3/0 source-ip 10.2.1.2 auto
#
return

PE3 configuration file

#
 sysname PE3
#
ip vpn-instance VPNA
 ipv4-family
  route-distinguisher 100:3
  apply-label per-instance
  vpn-target 111:1 export-extcommunity
  vpn-target 111:1 import-extcommunity
#
mpls lsr-id 4.4.4.4
#
mpls
#
mpls ldp
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 11.11.11.2 255.255.255.0
 mpls
 mpls ldp
#
interface GigabitEthernet0/2/0
 undo shutdown
 ip address 22.22.22.2 255.255.255.0
 mpls
 mpls ldp
#
interface GigabitEthernet0/3/0
 undo shutdown
 ip binding vpn-instance VPNA
 ip address 10.3.1.1 255.255.255.0
#
interface LoopBack1
 ip address 4.4.4.4 255.255.255.255
#
bgp 100
 peer 2.2.2.2 as-number 100
 peer 2.2.2.2 connect-interface LoopBack1
 peer 3.3.3.3 as-number 100
 peer 3.3.3.3 connect-interface LoopBack1
 #
 ipv4-family unicast
  undo synchronization
  peer 2.2.2.2 enable
  peer 3.3.3.3 enable
 #
 ipv4-family vpnv4
  policy vpn-target
  peer 2.2.2.2 enable
  peer 3.3.3.3 enable
 #
 ipv4-family vpn-instance VPNA
  peer 10.3.1.2 as-number 65410
  import-route direct
  maximum load-balancing 2
#
ospf 1
 area 0.0.0.0
  network 11.11.11.0 0.0.0.255
  network 22.22.22.0 0.0.0.255
  network 4.4.4.4 0.0.0.0
#
return

CE1 configuration file

#
 sysname CE1
#
 bfd
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 10.1.1.1 255.255.255.0
#
interface GigabitEthernet0/2/0
 undo shutdown
 ip address 10.2.1.1 255.255.255.0
#
interface LoopBack1
 ip address 1.1.1.1 255.255.255.255
#
 load-balance packet all
#
 ip route-static 0.0.0.0 0.0.0.0 10.1.1.2
 ip route-static 0.0.0.0 0.0.0.0 10.2.1.2
#
bfd ce1_to_pe1 bind peer-ip 10.1.1.2 interface GigabitEthernet0/1/0 source-ip 10.1.1.1 auto
#
bfd ce1_to_pe2 bind peer-ip 10.2.1.2 interface GigabitEthernet0/2/0 source-ip 10.2.1.1 auto
#
return

CE2 configuration file

#
 sysname CE2
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 10.3.1.2 255.255.255.0
#
bgp 65410
 peer 10.3.1.1 as-number 100
 #
 ipv4-family unicast
  undo synchronization
  import-route direct
  peer 10.3.1.1 enable
#
return

Example for Configuring Multi-hop BFD

This section provides an example for configuring multi-hop BFD to rapidly monitor a multi-hop link on a network.

Networking Requirements

BFD sessions can be established to rapidly monitor multi-hop links. As shown in Figure 3-8, BFD in asynchronous mode is configured to monitor the multi-hop link between Device A and Device C.

Figure 3-8 Multi-hop BFD

Interfaces 1 through 2 in this example are GE 0/1/0, GE 0/2/0, respectively.

Precautions

BFD sessions must be established on both ends.

Configuration Roadmap

The configuration roadmap is as follows:

Configure a BFD session on Device A to monitor the multi-hop link from Device A to Device C.
Configure a BFD session on Device C to monitor the multi-hop link from Device C to Device A.

Data Preparation

To complete the configuration, you need the following data:

Peer IP address monitored by BFD
Names of the BFD sessions for detecting the multi-hop link
Local and remote discriminators of BFD sessions

Procedure

Configure Device A, Device B, and Device C to be routable.

# Assign an IP address to the interface on Device A.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceA

[*HUAWEI] commit

[~DeviceA] interface GigabitEthernet 0/1/0

[~DeviceA-GigabitEthernet0/1/0] undo shutdown

[*DeviceA-GigabitEthernet0/1/0] ip address 10.1.1.1 24

[*DeviceA-GigabitEthernet0/1/0] commit

[~DeviceA-GigabitEthernet0/1/0] quit

# Assign IP addresses to the interfaces on Device B.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceB

[*HUAWEI] commit

[~DeviceB] interface GigabitEthernet 0/1/0

[~DeviceB-GigabitEthernet0/1/0] undo shutdown

[*DeviceB-GigabitEthernet0/1/0] ip address 10.1.1.2 24

[*DeviceB-GigabitEthernet0/1/0] commit

[~DeviceB-GigabitEthernet0/1/0] quit

[~DeviceB] interface GigabitEthernet 0/2/0

[~DeviceB-GigabitEthernet0/2/0] undo shutdown

[*DeviceB-GigabitEthernet0/2/0] ip address 10.2.1.1 24

[*DeviceB-GigabitEthernet0/2/0] commit

[~DeviceB-GigabitEthernet0/2/0] quit

# Assign an IP address to the interface on Device C.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceC

[*HUAWEI] commit

[~DeviceC] interface GigabitEthernet 0/1/0

[~DeviceC-GigabitEthernet0/1/0] undo shutdown

[*DeviceC-GigabitEthernet0/1/0] ip address 10.2.1.2 24

[*DeviceC-GigabitEthernet0/1/0] commit

[~DeviceC-GigabitEthernet0/1/0] quit

# Configure static routes.

[~DeviceA] ip route-static 10.2.1.0 255.255.255.0 10.1.1.2

[*DeviceA] commit

[~DeviceC] ip route-static 10.1.1.0 255.255.255.0 10.2.1.1

[*DeviceC] commit

Configure BFD to monitor the multi-hop link between Device A and Device C.

# Enable BFD on Device A and establish a BFD session to monitor the link from Device A to Device C. You do not need to bind the BFD session to an interface.

[~DeviceA] bfd

[*DeviceA-bfd] quit

[*DeviceA] bfd atoc bind peer-ip 10.2.1.2

[*DeviceA-bfd-session-atoc] discriminator local 10

[*DeviceA-bfd-session-atoc] discriminator remote 20

[*DeviceA-bfd-session-atoc] commit

[~DeviceA-bfd-session-atoc] quit

# Enable BFD on Device C and establish a BFD session to monitor the link from Device C to Device A. You do not need to bind the BFD session to an interface.

[~DeviceC] bfd

[*DeviceC-bfd] quit

[*DeviceC] bfd ctoa bind peer-ip 10.1.1.1

[*DeviceC-bfd-session-ctoa] discriminator local 20

[*DeviceC-bfd-session-ctoa] discriminator remote 10

[*DeviceC-bfd-session-ctoa] commit

[~DeviceC-bfd-session-ctoa] quit

Verify the configuration.

After completing the configurations, run the display bfd session all verbose command on Device A and Device C. The command output shows that a multi-hop BFD session has been established and its status is Up.

The following example uses the command output on Device A.

[~DeviceA] display bfd session all verbose

(w): State in WTR 
(*): State is invalid
------------------------------------------------------------------------------
  (Multi Hop)  State : Up                       Name : atoc
------------------------------------------------------------------------------
  Local Discriminator    : 10             Remote Discriminator    : 20
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Peer Ip Address
  Bind Session Type      : Static
  Bind Peer IP Address   : 10.2.1.2
  Bind Interface         : -   
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 4784             TTL                    : 254  
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : 2584985432       Session Detect TmrID   : -
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------
       Total UP/DOWN Session Number : 1/0

# Run the shutdown command on GE 0/1/0 of Device A to simulate a link fault.

[~DeviceA] interface GigabitEthernet 0/1/0

[~DeviceA-GigabitEthernet0/1/0] shutdown

[*DeviceA-GigabitEthernet0/1/0] commit

[~DeviceA-GigabitEthernet0/1/0] quit

Run the display bfd session all verbose command on Router A. The command output shows that the status of the BFD session is Down.

The following example uses the command output on Device A.

[~DeviceA] display bfd session all verbose

(w): State in WTR 
(*): State is invalid
------------------------------------------------------------------------------
  (Multi Hop)  State : Down                       Name : atoc
------------------------------------------------------------------------------
  Local Discriminator    : 10             Remote Discriminator    : 20
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Peer Ip Address
  Bind Session Type      : Static
  Bind Peer IP Address   : 10.2.1.2
  Bind Interface         : -   
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 4784             TTL                    : 254  
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : 2584985432       Session Detect TmrID   : -
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------
       Total UP/DOWN Session Number : 0/1

Configuration Files

Device A configuration file

 sysname DeviceA

bfd

interface GigabitEthernet0/1/0

 undo shutdown

 ip address 10.1.1.1 255.255.255.0

#
ip route-static 10.2.1.0 255.255.255.0 10.1.1.2

bfd atoc bind peer-ip 10.2.1.2

 discriminator local 10

 discriminator remote 20

return

Device B configuration file

 sysname DeviceB

interface GigabitEthernet0/1/0

 undo shutdown

 ip address 10.1.1.2 255.255.255.0

interface GigabitEthernet0/2/0

 undo shutdown

 ip address 10.2.1.1 255.255.255.0

return

Device C configuration file

 sysname DeviceC

bfd

interface GigabitEthernet0/1/0

 undo shutdown

 ip address 10.2.1.2 255.255.255.0

#
ip route-static 10.1.1.0 255.255.255.0 10.2.1.1

bfd ctoa bind peer-ip 10.1.1.1

 discriminator local 20

 discriminator remote 10

return

Example for Configuring Single-hop BFD for IPv6

This section provides an example for configuring single-hop BFD for IPv6 to detect faults in an IPv6 link on a network.

Networking Requirements

To rapidly detect faults in an IPv6 link on a network, establish a single-hop BFD session for IPv6. On the network shown in Figure 3-9, a single-hop BFD session in asynchronous mode is established to detect faults in the link between Device A and Device B.

Figure 3-9 Single-hop BFD for IPv6

Interfaces 1 in this example are GE 0/1/0.

Precautions

BFD sessions for IPv6 must be established on both ends.

Configuration Roadmap

The configuration roadmap is as follows:

Enable BFD globally on Device A and Device B.
Create single-hop BFD sessions for IPv6 and bind them to the outbound interfaces on Device A and Device B.

Data Preparation

To complete the configuration, you need the following data:

Peer IPv6 address monitored by BFD
Local and remote discriminators of BFD sessions
BFD session names

Procedure

Assign IPv6 addresses to interfaces connecting Device A and Device B.

# Assign an IPv6 address to the interface on Device A.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceA

[*HUAWEI] commit

[~DeviceA] interface gigabitethernet 0/1/0

[~DeviceA-GigabitEthernet0/1/0] undo shutdown

[*DeviceA-GigabitEthernet0/1/0] ipv6 enable

[*DeviceA-GigabitEthernet0/1/0] ipv6 address 2001:db8::1 32

[*DeviceA-GigabitEthernet0/1/0] commit

[~DeviceA-GigabitEthernet0/1/0] quit

# Assign an IPv6 address to the interface on Device B.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceB

[*HUAWEI] commit

[~DeviceB] interface gigabitethernet 0/1/0

[~DeviceB-GigabitEthernet0/1/0] undo shutdown

[*DeviceB-GigabitEthernet0/1/0] ipv6 enable

[*DeviceB-GigabitEthernet0/1/0] ipv6 address 2001:db8::2 32

[*DeviceB-GigabitEthernet0/1/0] commit

[~DeviceB-GigabitEthernet0/1/0] quit

After the configuration is complete, Device A and Device B can ping each other. The following example uses the command output on Device A.

[~DeviceA] ping ipv6 2001:db8::2

PING 2001:db8::2 : 56  data bytes, press CTRL_C to break
    Reply from 2001:db8::2
    bytes=56 Sequence=1 hop limit=64 time=3 ms
    Reply from 2001:db8::2
    bytes=56 Sequence=2 hop limit=64 time=1 ms
    Reply from 2001:db8::2
    bytes=56 Sequence=3 hop limit=64 time=1 ms
    Reply from 2001:db8::2
    bytes=56 Sequence=4 hop limit=64 time=1 ms
    Reply from 2001:db8::2
    bytes=56 Sequence=5 hop limit=64 time=1 ms
  ---2001:db8::2 ping statistics---
    5 packet(s) transmitted
    5 packet(s) received
    0.00% packet loss
    round-trip min/avg/max=1/1/3 ms

Configure single-hop BFD for IPv6.

# Configure Device A.

[~DeviceA] bfd

[*DeviceA-bfd] quit

[*DeviceA] bfd ipv6session bind peer-ipv6 2001:db8::2 interface gigabitethernet 0/1/0

[*DeviceA-bfd-session-ipv6session] discriminator local 1

[*DeviceA-bfd-session-ipv6session] discriminator remote 2

[*DeviceA-bfd-session-ipv6session] commit

[~DeviceA-bfd-session-ipv6session] quit

# Configure Device B.

[~DeviceB] bfd

[*DeviceB-bfd] quit

[*DeviceB] bfd ipv6session bind peer-ipv6 2001:db8::1 interface gigabitethernet 0/1/0

[*DeviceB-bfd-session-ipv6session] discriminator local 2

[*DeviceB-bfd-session-ipv6session] discriminator remote 1

[*DeviceB-bfd-session-ipv6session] commit

[~DeviceB-bfd-session-ipv6session] quit

Verify the configuration.

After completing the configurations, run the display bfd session all verbose command on Device A or Device B. The command output shows that a single-hop BFD session for IPv6 has been established and its status is Up. The following example uses the command output on Device A.

[~DeviceA] display bfd session all verbose

(w): State in WTR 
(*): State is invalid
------------------------------------------------------------------------------
  (One Hop)   State : Up                    Name : ipv6session
------------------------------------------------------------------------------
  Local Discriminator    : 1                Remote Discriminator   : 2
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(GigabitEthernet0/1/0)
  Bind Session Type      : Static
  Bind Peer IP Address   : 2001:db8::2
  Bind Interface         : GigabitEthernet0/1/0
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : 0                Session Detect TmrID   : 0
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 1/0

Configuration Files

Device A configuration file

#
sysname DeviceA
#
bfd
#
interface GigabitEthernet0/1/0
 undo shutdown
 ipv6 enable
 ipv6 address 2001:db8::1/32
#
bfd ipv6session bind peer-ipv6 2001:db8::2 interface GigabitEthernet0/1/0
 discriminator local 1
 discriminator remote 2
#
return

Device B configuration file

#
sysname DeviceB
#
bfd
#
interface GigabitEthernet0/1/0
 undo shutdown
 ipv6 enable
 ipv6 address 2001:db8::2/32
#
bfd ipv6session bind peer-ipv6 2001:db8::1 interface GigabitEthernet0/1/0
 discriminator local 2
 discriminator remote 1
#
return

Example for Configuring Multi-hop BFD for IPv6

This section provides an example for configuring multi-hop BFD for IPv6 to detect faults in an IPv6 link on a network.

Networking Requirements

To rapidly detect faults in an IPv6 link on a network, establish a multi-hop BFD session for IPv6. On the network shown in Figure 3-10, a multi-hop BFD session in asynchronous mode is established to detect faults in the link between Device A and Device C.

Figure 3-10 Multi-hop BFD for IPv6

Interfaces 1 and 2 in this example represent GE 0/1/0, and GE 0/2/0, respectively.

Precautions

BFD sessions for IPv6 must be established on both ends.

Configuration Roadmap

The configuration roadmap is as follows:

Enable BFD globally on Device A and Device C.
Configure multi-hop BFD for IPv6 on Device A to detect faults in the link from Device A to Device C.
Configure multi-hop BFD for IPv6 on Device C to detect faults in the link from Device C to Device A.

Data Preparation

To complete the configuration, you need the following data:

Peer IPv6 address monitored by BFD
Local and remote discriminators of BFD sessions
BFD session names

Procedure

Assign an IPv6 address to each interface on Device A, Device B, and Device C, and configure Open Shortest Path First version 3 (OSPFv3) to ensure that these devices communicate with each other.

# Configure Device A.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceA

[*HUAWEI] commit

[~DeviceA] ospfv3 1

[*DeviceA-ospfv3-1] router-id 1.1.1.1

[*DeviceA-ospfv3-1] area 0

[*DeviceA-ospfv3-1-area-0.0.0.0] quit

[*DeviceA-ospfv3-1] quit

[DeviceA] interface gigabitethernet 0/1/0

[*DeviceA-GigabitEthernet0/1/0] undo shutdown

[*DeviceA-GigabitEthernet0/1/0] ipv6 enable

[*DeviceA-GigabitEthernet0/1/0] ipv6 address 2001:db8:1::1 64

[*DeviceA-GigabitEthernet0/1/0] ospfv3 1 area 0

[*DeviceA-GigabitEthernet0/1/0] commit

[~DeviceA-GigabitEthernet0/1/0] quit

# Configure Device B.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceB

[*HUAWEI] commit

[~DeviceB] ospfv3 1

[*DeviceB-ospfv3-1] router-id 2.2.2.2

[*DeviceB-ospfv3-1] area 0

[*DeviceB-ospfv3-1-area-0.0.0.0] quit

[*DeviceB-ospfv3-1] quit

[~DeviceB] interface gigabitethernet 0/1/0

[*DeviceB-GigabitEthernet0/1/0] undo shutdown

[*DeviceB-GigabitEthernet0/1/0] ipv6 enable

[*DeviceB-GigabitEthernet0/1/0] ipv6 address 2001:db8:1::2 64

[*DeviceB-GigabitEthernet0/1/0] ospfv3 1

[*DeviceB-GigabitEthernet0/1/0] commit

[~DeviceB-GigabitEthernet0/1/0] quit

[~DeviceB] interface gigabitethernet 0/2/0

[~DeviceB-GigabitEthernet0/2/0] undo shutdown

[*DeviceB-GigabitEthernet0/2/0] ipv6 enable

[*DeviceB-GigabitEthernet0/2/0] ipv6 address 2001:db8:2::1 64

[*DeviceB-GigabitEthernet0/2/0] ospfv3 1 area 0

[*DeviceB-GigabitEthernet0/2/0] commit

[~DeviceB-GigabitEthernet0/2/0] quit

# Configure Device C.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceC

[*HUAWEI] commit

[~DeviceC] ospfv3 1

[*DeviceC-ospfv3-1] router-id 3.3.3.3

[*DeviceC-ospfv3-1] area 0

[*DeviceC-ospfv3-1-area-0.0.0.0] quit

[*DeviceC-ospfv3-1] quit

[~DeviceC] interface gigabitethernet 0/2/0

[*DeviceC-GigabitEthernet0/2/0] undo shutdown

[*DeviceC-GigabitEthernet0/2/0] ipv6 enable

[*DeviceC-GigabitEthernet0/2/0] ipv6 address 2001:db8:2::2 64

[*DeviceC-GigabitEthernet0/2/0] ospfv3 1 area 0

[*DeviceC-GigabitEthernet0/2/0] commit

[~DeviceC-GigabitEthernet0/2/0] quit

After the configuration is complete, Device A and Device C can ping each other. The following example uses the command output on Device A.

[~DeviceA] ping ipv6 2001:db8:2::2

PING 2001:db8:2::2 : 56  data bytes, press CTRL_C to break
    Reply from 2001:db8:2::2
    bytes=56 Sequence=1 hop limit=64 time=22 ms
    Reply from 2001:db8:2::2
    bytes=56 Sequence=2 hop limit=64 time=1 ms
    Reply from 2001:db8:2::2
    bytes=56 Sequence=3 hop limit=64 time=1 ms
    Reply from 2001:db8:2::2
    bytes=56 Sequence=4 hop limit=64 time=1 ms

    Reply from 2001:db8:2::2
    bytes=56 Sequence=5 hop limit=64 time=1 ms
  ---2001:db8:2::2 ping statistics---
    5 packet(s) transmitted
    5 packet(s) received
    0.00% packet loss
    round-trip min/avg/max=1/5/22 ms

Configure multi-hop BFD for IPv6 on Device A and Device C.

# Configure Device A.

[~DeviceA] bfd

[*DeviceA-bfd] quit

[*DeviceA] bfd ipv6session bind peer-ipv6 2001:db8:2::2

[*DeviceA-bfd-session-ipv6session] discriminator local 1

[*DeviceA-bfd-session-ipv6session] discriminator remote 2

[*DeviceA-bfd-session-ipv6session] commit

[~DeviceA-bfd-session-ipv6session] quit

# Configure Device C.

[~DeviceC] bfd

[*DeviceC-bfd] quit

[*DeviceC] bfd ipv6session bind peer-ipv6 2001:db8:1::1

[*DeviceC-bfd-session-ipv6session] discriminator local 2

[*DeviceC-bfd-session-ipv6session] discriminator remote 1

[*DeviceC-bfd-session-ipv6session] commit

[~DeviceC-bfd-session-ipv6session] quit

Verify the configuration.

After completing the configurations, run the display bfd session all verbose command on Device A or Device C. The command output shows that a multi-hop BFD session for IPv6 has been established and its status is Up. The following example uses the command output on Device A.

[~DeviceA] display bfd session all verbose

(w): State in WTR  (*): State is invalid
------------------------------------------------------------------------------
  (Multi Hop) State : UP                  Name : ipv6session
------------------------------------------------------------------------------
  Local Discriminator    : 1                Remote Discriminator   : 2
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Peer IP Address
  Bind Session Type      : Static
  Bind Peer IP Address   : 2001:db8:2::2
  Bind Interface         : -
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 4784             TTL                    : 254
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : 2720409460       Session Detect TmrID   : -
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 1/0

Configuration Files

Device A configuration file

#
sysname DeviceA
#
bfd
#
ospfv3 1
 router-id 1.1.1.1
 area 0.0.0.0
#
interface GigabitEthernet0/1/0
 undo shutdown
 ipv6 enable
 ipv6 address 2001:db8:1::1/64
 ospfv3 1 area 0.0.0.0
#
bfd ipv6session bind peer-ipv6 2001:db8:2::2
 discriminator local 1
 discriminator remote 2
return

Device B configuration file

#
sysname DeviceB
#
ospfv3 1
 router-id 2.2.2.2
 area 0.0.0.0
#
interface GigabitEthernet0/1/0
 undo shutdown
 ipv6 enable
 ipv6 address 2001:db8:1::2/64
 ospfv3 1 area 0.0.0.0
#
interface GigabitEthernet0/2/0
 undo shutdown
 ipv6 enable
 ipv6 address 2001:db8:2::1/64
 ospfv3 1 area 0.0.0.0
return

Device C configuration file

#
sysname DeviceC
#
bfd
#
ospfv3 1
 router-id 3.3.3.3
 area 0.0.0.0
#
interface GigabitEthernet0/2/0
 undo shutdown
 ipv6 enable
 ipv6 address 2001:db8:2::2/64
 ospfv3 1 area 0.0.0.0
#
bfd ipv6session bind peer-ipv6 2001:db8:1::1
 discriminator local 2
 discriminator remote 1
return

Example for Configuring Sub-Interfaces for QinQ VLAN Tag Termination to Support BFD

Sub-interfaces for QinQ VLAN tag termination are configured to support BFD on a typical network. In this manner, user packets with double tags can be reliably and stably sent over the network.

Networking Requirements

On the network shown in Figure 3-11, users of VLAN 10 access an ISP network through a default gateway. GE 0/2/0.1 is a sub-interface for QinQ VLAN tag termination on Device A, and GE 0/2/0.1 is a sub-interface for QinQ VLAN tag termination on Device B.

The networking requirements are as follows:

A BFD session is configured on Device A and Device B to monitor the link between Device A and Device B.
VRRP group 1 is configured on Device A and Device B. Device A functions as the master device and Device B functions as the backup device.
VRRP group 1 on Device A and Device B is configured to track the status of the BFD session.

Figure 3-11 Networking diagram for configuring sub-interfaces for QinQ VLAN tag termination to support BFD

Interfaces 1 and 2 in this example represent GE 0/1/0 and GE 0/2/0, respectively.

Sub-interface 2.1 in this example represents GE 0/2/0.1.

Configuration Roadmap

The configuration roadmap is as follows:

Configure an IGP to implement connectivity between Device A, Device B, and Device C.
Configure the Layer 2 forwarding function on switch 2.
Configure the QinQ function on switch 1.
Configure sub-interfaces for QinQ VLAN tag termination on Device A and Device B.
Configure a BFD session on Device A and Device B to monitor the link between Device A and Device B.
Configure VRRP group 1 on GE 0/2/0.1 of Device A and GE 0/2/0.1 of Device B. Ensure that Device A functions as the master device and Device B functions as the backup device.

Data Preparation

To complete the configuration, you need the following data:

Name of a BFD session
ID and virtual IP address of a VRRP group
VLAN IDs of sub-interfaces for QinQ VLAN tag termination

Procedure

Configure an IGP to implement connectivity between devices.

Assign IP addresses to interfaces as shown in Figure 3-11. Configure an IGP on Device A, Device B, and Device C. OSPF is used in this example.

# Configure Device A.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceA

[*HUAWEI] commit

[~DeviceA] interface gigabitethernet 0/1/0

[~DeviceA-GigabitEthernet0/1/0] undo shutdown

[*DeviceA-GigabitEthernet0/1/0] ip address 192.168.2.1 24

[*DeviceA-GigabitEthernet0/1/0] quit

[*DeviceA] interface gigabitethernet 0/2/0.1

[*DeviceA-GigabitEthernet0/2/0.1] undo shutdown

[*DeviceA-GigabitEthernet0/2/0.1] ip address 10.1.1.1 24

[*DeviceA-GigabitEthernet0/2/0.1] quit

[*DeviceA] ospf 1

[*DeviceA-ospf-1] area 0

[*DeviceA-ospf-1-area-0.0.0.0] network 192.168.2.0 0.0.0.255

[*DeviceA-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255

[*DeviceA-ospf-1-area-0.0.0.0] commit

[~DeviceA-ospf-1-area-0.0.0.0] quit

[~DeviceA-ospf-1] quit

# Configure Device B.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceB

[*HUAWEI] commit

[~DeviceB] interface gigabitethernet 0/1/0

[~DeviceB-GigabitEthernet0/1/0] undo shutdown

[*DeviceB-GigabitEthernet0/1/0] ip address 192.168.1.1 24

[*DeviceB-GigabitEthernet0/1/0] quit

[*DeviceB] interface gigabitethernet 0/2/0.1

[*DeviceB-GigabitEthernet0/2/0.1] undo shutdown

[*DeviceB-GigabitEthernet0/2/0.1] ip address 10.1.1.2 24

[*DeviceB-GigabitEthernet0/2/0.1] quit

[*DeviceB] ospf 1

[*DeviceB-ospf-1] area 0

[*DeviceB-ospf-1-area-0.0.0.0] network 192.168.1.0 0.0.0.255

[*DeviceB-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255

[*DeviceB-ospf-1-area-0.0.0.0] commit

[~DeviceB-ospf-1-area-0.0.0.0] quit

[~DeviceB-ospf-1] quit

# Configure Device C.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceC

[*HUAWEI] commit

[~DeviceC] interface gigabitethernet 0/1/0

[~DeviceC-GigabitEthernet0/1/0] undo shutdown

[*DeviceC-GigabitEthernet0/1/0] ip address 192.168.2.2 24

[*DeviceC-GigabitEthernet0/1/0] quit

[*DeviceC] interface gigabitethernet 0/2/0

[*DeviceC-GigabitEthernet0/2/0] undo shutdown

[*DeviceC-GigabitEthernet0/2/0] ip address 192.168.1.2 24

[*DeviceC-GigabitEthernet0/2/0] quit

[*DeviceC] ospf 1

[*DeviceC-ospf-1] area 0

[*DeviceC-ospf-1-area-0.0.0.0] network 192.168.1.0 0.0.0.255

[*DeviceC-ospf-1-area-0.0.0.0] network 192.168.2.0 0.0.0.255

[*DeviceC-ospf-1-area-0.0.0.0] commit

[~DeviceC-ospf-1-area-0.0.0.0] quit

[~DeviceC-ospf-1] quit

After completing the preceding configuration, run the display ip routing-table command on each Device. The command output shows that OSPF correctly calculates routes between Device A and Device B. Device A and Device B can ping each other.

The command output on Device A is used as an example.

<DeviceA> display ip routing-table

Route Flags: R - relay, D - download to fib, T - to vpn-instance, B - black hole route
------------------------------------------------------------------------------
Routing Tables: Public
         Destinations : 7       Routes : 7

Destination/Mask    Proto  Pre  Cost       Flags NextHop         Interface
    192.168.2.0/24  Direct 0    0            D   192.168.2.1     GigabitEthernet0/1/0
    192.168.2.1/32  Direct 0    0            D   127.0.0.1       InLoopBack0
    192.168.1.0/24  OSPF   10   2            D   192.168.2.2     GigabitEthernet0/1/0
       10.1.1.0/24  Direct 0    0            D   10.1.1.1        GigabitEthernet0/2/0.1
       10.1.1.1/32  Direct 0    0            D   127.0.0.1       InLoopBack0
      127.0.0.0/8   Direct 0    0            D   127.0.0.1       InLoopBack0
      127.0.0.1/32  Direct 0    0            D   127.0.0.1       InLoopBack0

[~DeviceA] ping 192.168.1.1

PING 192.168.1.1: 56  data bytes, press CTRL_C to break
    Reply from 192.168.1.1: bytes=56 Sequence=1 ttl=254 time=7 ms
    Reply from 192.168.1.1: bytes=56 Sequence=2 ttl=254 time=1 ms
    Reply from 192.168.1.1: bytes=56 Sequence=3 ttl=254 time=5 ms
    Reply from 192.168.1.1: bytes=56 Sequence=4 ttl=254 time=1 ms
    Reply from 192.168.1.1: bytes=56 Sequence=5 ttl=254 time=8 ms

  --- 192.168.1.1 ping statistics ---
    5 packet(s) transmitted
    5 packet(s) received
    0.00% packet loss
    round-trip min/avg/max = 1/4/8 ms

Configure the Layer 2 forwarding function on switch 2.

<HUAWEI> system-view

[~HUAWEI] sysname Switch2

[*HUAWEI] commit

[~Switch2] vlan 10

[*Switch2-vlan10] port gigabitethernet 0/2/0

[*Switch2-vlan10] quit

[*Switch2] interface gigabitethernet 0/1/0

[*Switch2-GigabitEthernet0/1/0] undo shutdown

[*Switch2-GigabitEthernet0/1/0] port trunk allow-pass vlan 10

[*Switch2-GigabitEthernet0/1/0] commit

[~Switch2-GigabitEthernet0/1/0] quit

Configure the QinQ function to allow switch 1 to send packets with double tags to Device A and Device B.

<HUAWEI> system-view

[~HUAWEI] sysname Switch1

[*HUAWEI] commit

[~Switch1] vlan 100

[*Switch1-vlan100] quit

[*Switch1] interface gigabitethernet 0/1/0

[*Switch1-GigabitEthernet0/1/0] port vlan-stacking vlan 10 stack-vlan 100

[*Switch1-GigabitEthernet0/1/0] undo shutdown

[*Switch1-GigabitEthernet0/1/0] quit

[*Switch1] interface gigabitethernet 0/1/1

[*Switch1-GigabitEthernet0/1/1] port trunk allow-pass vlan 100

[*Switch1-GigabitEthernet0/1/1] undo shutdown

[*Switch1-GigabitEthernet0/1/1] quit

[*Switch1] interface gigabitethernet 0/1/2

[*Switch1-GigabitEthernet0/1/2] port trunk allow-pass vlan 100

[*Switch1-GigabitEthernet0/1/2] undo shutdown

[*Switch1-GigabitEthernet0/1/2] commit

[~Switch1-GigabitEthernet0/1/2] quit

Configure a sub-interface for QinQ VLAN tag termination on each Device.

# Configure Device A.

[~DeviceA] interface gigabitethernet 0/2/0.1

[*DeviceA-GigabitEthernet0/2/0.1] control-vid 1 qinq-termination

[*DeviceA-GigabitEthernet0/2/0.1] qinq termination pe-vid 100 ce-vid 10

[*DeviceA-GigabitEthernet0/2/0.1] commit

# Configure Device B.

[~DeviceB] interface gigabitethernet 0/2/0.1

[*DeviceB-GigabitEthernet0/2/0.1] control-vid 1 qinq-termination

[*DeviceB-GigabitEthernet0/2/0.1] qinq termination pe-vid 100 ce-vid 10

[*DeviceB-GigabitEthernet0/2/0.1] commit

Configure a BFD session.

# Configure Device A.

[~DeviceA] bfd

[*DeviceA-bfd] quit

[*DeviceA] bfd atob bind peer-ip default-ip interface gigabitethernet 0/2/0.1

[*DeviceA-bfd-session-atob] discriminator local 1

[*DeviceA-bfd-session-atob] discriminator remote 2

[*DeviceA-bfd-session-atob] qinq pe-vid 100 ce-vid 10

[*DeviceA-bfd-session-atob] commit

[~DeviceA-bfd-session-atob] quit

# Configure Device B.

[~DeviceB] bfd

[*DeviceB-bfd] quit

[*DeviceB] bfd atob bind peer-ip default-ip interface gigabitethernet 0/2/0.1

[*DeviceB-bfd-session-atob] discriminator local 2

[*DeviceB-bfd-session-atob] discriminator remote 1

[*DeviceB-bfd-session-atob] qinq pe-vid 100 ce-vid 10

[*DeviceB-bfd-session-atob] commit

[~DeviceB-bfd-session-atob] quit

After completing the preceding configuration, run the display bfd session all verbose command on each Device. The command output shows that the BFD session is UP. The command output on Device A is used as an example.

[~DeviceA] display bfd session all verbose

(w): State in WTR  (*): State is invalid
--------------------------------------------------------------------------------
  (One Hop)   State : UP                  Name : atob
--------------------------------------------------------------------------------
  Local Discriminator    : 1                Remote Discriminator   : 2
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(0/2/0)  
  Bind Session Type      : Static 
  Bind Peer IP Address   : 10.1.1.2      
  Bind Interface         : 0/2/0                            
  Pe-vid                 : 100              Ce-vid                 : 10  
  FSM Board Id           : 6                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10 
  Local Detect Multi     : 50               Detect Interval (ms)   : 500 
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255 
  Proc Interface Status  : Disable          Process PST            : Disable    
  WTR Interval (ms)      : -                Config PST             : Disable    
  Active Multi           : 50   
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : -                Session Detect TmrID   : - 
  Session Init TmrID     : -                Session WTR TmrID      : - 
  Session Echo Tx TmrID  : -   
  Session Description    : - 
------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 1/0

Configure VRRP group 1 to track the status of the BFD session.

# Configure Device A.

[~DeviceA] interface gigabitethernet 0/2/0.1

[*DeviceA-GigabitEthernet0/2/0.1] qinq vrrp pe-vid 100 ce-vid 10

[*DeviceA-GigabitEthernet0/2/0.1] vrrp vrid 1 virtual-ip 10.1.1.100

[*DeviceA-GigabitEthernet0/2/0.1] vrrp vrid 1 priority 160

[*DeviceA-GigabitEthernet0/2/0.1] vrrp vrid 1 track bfd-session 1

[*DeviceA-GigabitEthernet0/2/0.1] arp broadcast enable

[*DeviceA-GigabitEthernet0/2/0.1] commit

[~DeviceA-GigabitEthernet0/2/0.1] quit

# Configure Device B.

[~DeviceB] interface gigabitethernet 0/2/0.1

[*DeviceB-GigabitEthernet0/2/0.1] qinq vrrp pe-vid 100 ce-vid 10

[*DeviceB-GigabitEthernet0/2/0.1] vrrp vrid 1 virtual-ip 10.1.1.100

[*DeviceB-GigabitEthernet0/2/0.1] vrrp vrid 1 track bfd-session 2

[*DeviceB-GigabitEthernet0/2/0.1] arp broadcast enable

[*DeviceB-GigabitEthernet0/2/0.1] commit

[~DeviceB-GigabitEthernet0/2/0.1] quit

Verify the configuration.

After completing the preceding configuration, run the display vrrp command on each Device. The command output shows that the status of the BFD session tracked by VRRP group 1 is UP. The command output on Device A is used as an example.

[~DeviceA] display vrrp

GigabitEthernet0/1/0 | Virtual Device 1
State             : Master
Virtual IP        : 10.1.1.100
Master IP         : 192.168.2.1
Local IP          : 192.168.2.1
PriorityRun       : 160
PriorityConfig    : 160
MasterPriority    : 160
Preempt           : YES                     Delay Time : 0s
Hold Multiplier   : 4
TimerRun          : 1s
TimerConfig       : 1s
Auth Type         : NONE
Virtual MAC       : 00e0-fc12-7890
Check TTL         : YES
Config Type       : normal-vrrp
Backup-forward    : disabled
Track IF          : GigabitEthernet0/1/0Priority Reduced :20
IF State          : DOWN
Track BFD         : 0                Priority Reduced :10
BFD-Session State : UP
Create Time         : 2011-12-29 05:41:23
Last Change Time    : 2011-12-29 05:41:33

Configuration Files

Device A configuration file

#
 sysname DeviceA
#
bfd
#
interface GigabitEthernet 0/1/0
 undo shutdown
 ip address 192.168.2.1 24
#
interface GigabitEthernet0/2/0.1
 undo shutdown
 encapsulation qinq-termination
 qinq termination pe-vid 100 ce-vid 10
 qinq vrrp pe-vid 100 ce-vid 10
 ip address 10.1.1.1 24
 vrrp vrid 1 virtual-ip 10.1.1.100
 vrrp vrid 1 priority 160
 vrrp vrid 1 track bfd-session 1
 arp broadcast enable
#
bfd atob bind peer-ip default-ip interface gigabitethernet 0/2/0.1
 discriminator local 1
 discriminator remote 2
 qinq pe-vid 100 ce-vid 10
 commit
#
ospf 1
 area 0.0.0.0
 network 192.168.2.0 0.0.0.255
 network 10.1.1.0 0.0.0.255
#
return

Device B configuration file

#
 sysname DeviceB
#
bfd
#
interface GigabitEthernet 0/1/0
 undo shutdown
 ip address 192.168.1.1 24
#
interface GigabitEthernet0/2/0.1
 undo shutdown
 encapsulation qinq-termination
 qinq termination pe-vid 100 ce-vid 10
 qinq vrrp pe-vid 100 ce-vid 10
 ip address 10.1.1.2 24
 vrrp vrid 1 virtual-ip 10.1.1.100
 vrrp vrid 1 track bfd-session 2
 arp broadcast enable
#
bfd atob bind peer-ip default-ip interface gigabitethernet 0/2/0.1
 discriminator local 2
 discriminator remote 1
 qinq pe-vid 100 ce-vid 10
 commit
#
ospf 1
 area 0.0.0.0
 network 192.168.1.0 0.0.0.255
 network 10.1.1.0 0.0.0.255
#
return

Device C configuration file

#
 sysname DeviceC
#
bfd
#
interface GigabitEthernet 0/1/0
 undo shutdown
 ip address 192.168.2.2 24
#
interface GigabitEthernet 0/2/0
 undo shutdown
 ip address 192.168.1.2 24
#
ospf 1
 area 0.0.0.0
 network 192.168.1.0 0.0.0.255
 network 192.168.2.0 0.0.0.255
#
return

Switch 1 configuration file

#
 sysname Switch1
#
vlan batch 100
#
interface GigabitEthernet0/1/0
 undo shutdown
 port vlan-stacking vlan 10 stack-vlan 100
#
interface GigabitEthernet0/1/1
 undo shutdown
 port trunk allow-pass vlan 100
#
interface GigabitEthernet0/1/2
 undo shutdown
 port trunk allow-pass vlan 100
#
return

Switch 2 configuration file

#
 sysname Switch2
#
vlan batch 10
#
interface GigabitEthernet0/2/0
 undo shutdown
 port default vlan 10
#
interface GigabitEthernet0/1/0
 undo shutdown
 port trunk allow-pass vlan 10
#
return

Example for Configuring Sub-Interfaces for Dot1q VLAN Tag Termination to Support BFD

Sub-interfaces for dot1q VLAN tag termination are configured to support BFD on a typical network. In this manner, user packets with one tag can be reliably and stably sent over the network.

Networking Requirements

On the network shown in Figure 3-12, users of VLAN 10 access an ISP network through a default gateway. GE 0/2/0.1 is a sub-interface for dot1q VLAN tag termination on Device A, and GE 0/2/0.1 is a sub-interface for dot1q VLAN tag termination on Device B.

The networking requirements are as follows:

A BFD session is configured on Device A and Device B to monitor the link between Device A and Device B.
VRRP group 1 is configured on Device A and Device B. Device A functions as the master device and Device B functions as the backup device.
VRRP group 1 on Device A and Device B to track the status of the BFD session.

Figure 3-12 Networking diagram for configuring sub-interfaces for dot1q VLAN tag termination to support BFD

Interfaces 1 and 2 in this example represent GE 0/1/0 and GE 0/2/0, respectively.

Sub-interface 2.1 in this example represents GE 0/2/0.1.

Configuration Roadmap

The configuration roadmap is as follows:

Configure an IGP to implement connectivity between Device A, Device B, and Device C.
Configure the Layer 2 forwarding function on the switch.
Configure sub-interfaces for dot1q VLAN tag termination on Device A and Device B.
Configure a BFD session on Device A and Device B to monitor the link between Device A and Device B.
Configure VRRP group 1 on GE 0/2/0.1 of Device A and GE 0/2/0.1 of Device B. Device A functions as the master device and Device B functions as the backup device.

Data Preparation

To complete the configuration, you need the following data:

VLAN ID of a dot1q VLAN tag termination sub-interface
Name of a BFD session
ID and virtual IP address of a VRRP group

Procedure

Configure an IGP to implement connectivity between devices.

Assign IP addresses to interfaces as shown in Figure 3-12. Configure an IGP on Device A, Device B, and Device C. OSPF is used in this example.

# Configure Device A.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceA

[*HUAWEI] commit

[~DeviceA] interface gigabitethernet 0/1/0

[~DeviceA-GigabitEthernet0/1/0] undo shutdown

[*DeviceA-GigabitEthernet0/1/0] ip address 192.168.2.1 24

[*DeviceA-GigabitEthernet0/1/0] quit

[*DeviceA] interface gigabitethernet 0/2/0.1

[*DeviceA-GigabitEthernet0/2/0.1] undo shutdown

[*DeviceA-GigabitEthernet0/2/0.1] ip address 10.1.1.1 24

[*DeviceA-GigabitEthernet0/2/0.1] quit

[*DeviceA] ospf 1

[*DeviceA-ospf-1] area 0

[*DeviceA-ospf-1-area-0.0.0.0] network 192.168.2.0 0.0.0.255

[*DeviceA-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255

[*DeviceA-ospf-1-area-0.0.0.0] commit

[~DeviceA-ospf-1-area-0.0.0.0] quit

[~DeviceA-ospf-1] quit

# Configure Device B.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceB

[*HUAWEI] commit

[~DeviceB] interface gigabitethernet 0/1/0

[*DeviceB-GigabitEthernet0/1/0] undo shutdown

[*DeviceB-GigabitEthernet0/1/0] ip address 192.168.1.1 24

[*DeviceB-GigabitEthernet0/1/0] quit

[*DeviceB] interface gigabitethernet 0/2/0.1

[*DeviceB-GigabitEthernet0/2/0.1] undo shutdown

[*DeviceB-GigabitEthernet0/2/0.1] ip address 10.1.1.2 24

[*DeviceB-GigabitEthernet0/2/0.1] quit

[*DeviceB] ospf 1

[*DeviceB-ospf-1] area 0

[*DeviceB-ospf-1-area-0.0.0.0] network 192.168.1.0 0.0.0.255

[*DeviceB-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255

[*DeviceB-ospf-1-area-0.0.0.0] commit

[~DeviceB-ospf-1-area-0.0.0.0] quit

[~DeviceB-ospf-1] quit

# Configure Device C.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceC

[*HUAWEI] commit

[~DeviceC] interface gigabitethernet 0/1/0

[~DeviceC-GigabitEthernet0/1/0] undo shutdown

[*DeviceC-GigabitEthernet0/1/0] ip address 192.168.2.2 24

[*DeviceC-GigabitEthernet0/1/0] quit

[*DeviceC] interface gigabitethernet 0/2/0

[*DeviceC-GigabitEthernet0/2/0] undo shutdown

[*DeviceC-GigabitEthernet0/2/0] ip address 192.168.1.2 24

[*DeviceC-GigabitEthernet0/2/0] quit

[*DeviceC] ospf 1

[*DeviceC-ospf-1] area 0

[*DeviceC-ospf-1-area-0.0.0.0] network 192.168.1.0 0.0.0.255

[*DeviceC-ospf-1-area-0.0.0.0] network 192.168.2.0 0.0.0.255

[*DeviceC-ospf-1-area-0.0.0.0] commit

[~DeviceC-ospf-1-area-0.0.0.0] quit

[~DeviceC-ospf-1] quit

The command output on Device A is used as an example.

<DeviceA> display ip routing-table

Route Flags: R - relay, D - download to fib, T - to vpn-instance, B - black hole route
------------------------------------------------------------------------------
Routing Tables: Public
         Destinations : 7       Routes : 7

Destination/Mask    Proto  Pre  Cost       Flags NextHop         Interface
    192.168.2.0/24  Direct 0    0            D   192.168.2.1     GigabitEthernet0/1/0
    192.168.2.1/32  Direct 0    0            D   127.0.0.1       InLoopBack0
    192.168.1.0/24  OSPF   10   2            D   192.168.2.2     GigabitEthernet0/1/0
       10.1.1.0/24  Direct 0    0            D   10.1.1.1        GigabitEthernet0/2/0.1
       10.1.1.1/32  Direct 0    0            D   127.0.0.1       InLoopBack0
      127.0.0.0/8   Direct 0    0            D   127.0.0.1       InLoopBack0
      127.0.0.1/32  Direct 0    0            D   127.0.0.1       InLoopBack0

[~DeviceA] ping 192.168.1.1

PING 192.168.1.1: 56  data bytes, press CTRL_C to break
    Reply from 192.168.1.1: bytes=56 Sequence=1 ttl=254 time=7 ms
    Reply from 192.168.1.1: bytes=56 Sequence=2 ttl=254 time=1 ms
    Reply from 192.168.1.1: bytes=56 Sequence=3 ttl=254 time=5 ms
    Reply from 192.168.1.1: bytes=56 Sequence=4 ttl=254 time=1 ms
    Reply from 192.168.1.1: bytes=56 Sequence=5 ttl=254 time=8 ms

  --- 192.168.1.1 ping statistics ---
    5 packet(s) transmitted
    5 packet(s) received
    0.00% packet loss
    round-trip min/avg/max = 1/4/8 ms

Configure the Layer 2 forwarding function on the switch.

<HUAWEI> system-view

[~HUAWEI] sysname Switch

[*HUAWEI] commit

[~Switch] vlan 10

[*Switch-vlan10] port gigabitethernet 0/1/0

[*Switch-vlan10] quit

[*Switch] interface gigabitethernet 0/1/1

[*Switch-GigabitEthernet0/1/1] undo shutdown

[*Switch-GigabitEthernet0/1/1] port trunk allow-pass vlan 10

[*Switch-GigabitEthernet0/1/1] quit

[*Switch] interface gigabitethernet 0/1/2

[*Switch-GigabitEthernet0/1/2] undo shutdown

[*Switch-GigabitEthernet0/1/2] port trunk allow-pass vlan 10

[*Switch-GigabitEthernet0/1/2] commit

[~Switch-GigabitEthernet0/1/2] quit

Configure a sub-interface for dot1q VLAN tag termination on each Device.

# Configure Device A.

[~DeviceA] interface gigabitethernet 0/2/0.1

[*DeviceA-GigabitEthernet0/2/0.1] control-vid 1 dot1q-termination

[*DeviceA-GigabitEthernet0/2/0.1] dot1q termination vid 10

[*DeviceA-GigabitEthernet0/2/0.1] commit

# Configure Device B.

[~DeviceB] interface gigabitethernet 0/2/0.1

[*DeviceB-GigabitEthernet0/2/0.1] control-vid 1 dot1q-termination

[*DeviceB-GigabitEthernet0/2/0.1] dot1q termination vid 10

[*DeviceB-GigabitEthernet0/2/0.1] commit

Configure a BFD session.

# Configure Device A.

[~DeviceA] bfd

[*DeviceA-bfd] quit

[*DeviceA] bfd atob bind peer-ip default-ip interface gigabitethernet 0/2/0.1

[*DeviceA-bfd-session-atob] discriminator local 1

[*DeviceA-bfd-session-atob] discriminator remote 2

[*DeviceA-bfd-session-atob] dot1q vid 10

[*DeviceA-bfd-session-atob] commit

[~DeviceA-bfd-session-atob] quit

# Configure Device B.

[~DeviceB] bfd

[*DeviceB-bfd] quit

[*DeviceB] bfd atob bind peer-ip default-ip interface gigabitethernet 0/2/0.1

[*DeviceB-bfd-session-atob] discriminator local 2

[*DeviceB-bfd-session-atob] discriminator remote 1

[*DeviceB-bfd-session-atob] dot1q vid 10

[*DeviceB-bfd-session-atob] commit

[~DeviceB-bfd-session-atob] quit

After completing the configuration, run the display bfd session all verbose command. The command output shows that the BFD session is UP. The command output on Device A is used as an example.

[~DeviceA] display bfd session all verbose

(w): State in WTR  (*): State is invalid
--------------------------------------------------------------------------------
  (One Hop)   State : UP                  Name : atob
--------------------------------------------------------------------------------
  Local Discriminator    : 1                Remote Discriminator   : 2
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(0/2/0)  
  Bind Session Type      : Static 
  Bind Peer IP Address   : 10.1.1.2      
  Bind Interface         : 0/2/0                            
  Vid                    : 10  
  FSM Board Id           : 6                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10 
  Local Detect Multi     : 50               Detect Interval (ms)   : 500 
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255 
  Proc Interface Status  : Disable          Process PST            : Disable    
  WTR Interval (ms)      : -                Config PST             : Disable    
  Active Multi           : 50   
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : -                Session Detect TmrID   : - 
  Session Init TmrID     : -                Session WTR TmrID      : - 
  Session Echo Tx TmrID  : -   
  Session Description    : - 
--------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 1/0

Configure VRRP group 1 to track the status of the BFD session.

# Configure Device A.

[~DeviceA] interface gigabitethernet 0/2/0.1

[*DeviceA-GigabitEthernet0/2/0.1] dot1q vrrp vid 10

[*DeviceA-GigabitEthernet0/2/0.1] vrrp vrid 1 virtual 10.1.1.100

[*DeviceA-GigabitEthernet0/2/0.1] vrrp vrid 1 priority 160

[*DeviceA-GigabitEthernet0/2/0.1] vrrp vrid 1 track bfd-session 1

[*DeviceA-GigabitEthernet0/2/0.1] arp broadcast enable

[*DeviceA-GigabitEthernet0/2/0.1] commit

[~DeviceA-GigabitEthernet0/2/0.1] quit

# Configure Device B.

[~DeviceB] interface gigabitethernet 0/2/0.1

[*DeviceB-GigabitEthernet0/2/0.1] dot1q vrrp vid 10

[*DeviceB-GigabitEthernet0/2/0.1] vrrp vrid 1 virtual 10.1.1.100

[*DeviceB-GigabitEthernet0/2/0.1] vrrp vrid 1 track bfd-session 2

[*DeviceB-GigabitEthernet0/2/0.1] arp broadcast enable

[*DeviceB-GigabitEthernet0/2/0.1] commit

[~DeviceB-GigabitEthernet0/2/0.1] quit

Verify the configuration.

[~DeviceA] display vrrp

GigabitEthernet0/1/0 | Virtual Device 1
State             : Master
Virtual IP        : 10.1.1.100
Master IP         : 192.168.2.1
Local IP          : 192.168.2.1
PriorityRun       : 160
PriorityConfig    : 160
MasterPriority    : 160
Preempt           : YES                     Delay Time : 0s
Hold Multiplier   : 4
TimerRun          : 1s
TimerConfig       : 1s
Auth Type         : NONE
Virtual MAC       : 00e0-fc12-7890
Check TTL         : YES
Config Type       : normal-vrrp
Backup-forward    : disabled
Track IF          : GigabitEthernet0/1/0Priority Reduced :20
IF State          : DOWN
Track BFD         : 0                Priority Reduced :10
BFD-Session State : UP
Create Time         : 2011-12-29 05:41:23
Last Change Time    : 2011-12-29 05:41:33

Configuration Files

Device A configuration file

#
 sysname DeviceA
#
bfd
#
interface GigabitEthernet 0/1/0
 undo shutdown
 ip address 192.168.2.1 24
#
interface GigabitEthernet0/2/0
 undo shutdown
#
interface GigabitEthernet0/2/0.1
 undo shutdown
 encapsulation dot1q-termination
 dot1q termination vid 10
 dot1q vrrp vid 10
 ip address 10.1.1.1 24
 vrrp vrid 1 virtual 10.1.1.100
 vrrp vrid 1 priority 160
 vrrp vrid 1 track bfd-session 1
 arp broadcast enable
#
bfd atob bind peer-ip default-ip interface gigabitethernet 0/2/0.1
 discriminator local 1
 discriminator remote 2
 dot1q vid 10
 commit
#
ospf 1
 area 0.0.0.0
 network 192.168.2.0 0.0.0.255
 network 10.1.1.0 0.0.0.255
#
return

Device B configuration file

#
 sysname DeviceB
#
bfd
#
interface GigabitEthernet 0/1/0
 undo shutdown
 ip address 192.168.1.1 24
#
interface GigabitEthernet0/2/0
 undo shutdown
#
interface GigabitEthernet0/2/0.1
 undo shutdown
 encapsulation dot1q-termination
 dot1q termination vid 10
 dot1q vrrp vid 10
 ip address 10.1.1.2 24
 vrrp vrid 1 virtual 10.1.1.100
 vrrp vrid 1 track bfd-session 2
 arp broadcast enable
#
bfd atob bind peer-ip default-ip interface gigabitethernet 0/2/0.1
 discriminator local 2
 discriminator remote 1
 dot1q vid 10
 commit
#
ospf 1
 area 0.0.0.0
 network 192.168.1.0 0.0.0.255
 network 10.1.1.0 0.0.0.255
#
return

Device C configuration file

#
 sysname DeviceC
#
bfd
#
interface GigabitEthernet 0/1/0
 undo shutdown
 ip address 192.168.2.2 24
#
interface GigabitEthernet 0/2/0
 undo shutdown
 ip address 192.168.1.2 24
#
ospf 1
 area 0.0.0.0
 network 192.168.1.0 0.0.0.255
 network 192.168.2.0 0.0.0.255
#
return

Switch configuration file

#
 sysname Switch
#
vlan batch 10
#
interface GigabitEthernet0/1/0
 undo shutdown
 port default vlan 10
#
interface GigabitEthernet0/1/1
 undo shutdown
 port trunk allow-pass vlan 10
#
interface GigabitEthernet0/1/2
 undo shutdown
 port trunk allow-pass vlan 10
#
return

Example for Configuring a BFD for Link-Bundle Session to Detect Layer 3 Eth-Trunk Member Link Faults

This section provides an example for configuring a BFD for link-bundle session to monitor Layer 3 Eth-Trunk member links and rapidly detect link faults.

Networking Requirements

On the network shown in Figure 3-13, Device A and Device B are directly connected through Layer 3 Eth-Trunk interfaces. BFD sessions can be bound to Eth-Trunk interfaces to detect the connectivity of the Eth-Trunk between Device A and Device B. If single-hop BFD sessions are used, BFD selects one of the member links of the Eth-Trunk to monitor the status of the Eth-Trunk. Once BFD detects that the selected member link is Down, it considers the Eth-Trunk to be Down even if other member links of the Eth-Trunk are Up. To prevent BFD from incorrectly detecting the Eth-Trunk state, you can deploy BFD for link-bundle sessions instead of single-hop BFD sessions.

Figure 3-13 Configuring a BFD for link-bundle session to detect Eth-Trunk member link faults

Interfaces 1 through 2 in this example are GE 0/3/0, GE 0/3/1, respectively.

Configuration Roadmap

The configuration roadmap is as follows:

Create an Eth-Trunk interface on Device A and Device B, and add Ethernet physical interfaces to the Eth-Trunk interface.
Assign IP addresses to the Eth-Trunk interfaces on Device A and Device B so that Device A and Device B can interwork with each other through the Eth-Trunk interfaces.
Configure a BFD for link-bundle session on Device A and Device B to monitor the Eth-Trunk member links between Device A and Device B.

Data Preparation

To complete the configuration, you need the following data:

Numbers of the physical interfaces connecting Device A and Device B
IP addresses of the Eth-Trunk interfaces
Minimum interval at which BFD for link-bundle session packets are received

Procedure

Create an Eth-Trunk interface on Device A and Device B, and add Ethernet physical interfaces to the Eth-Trunk interface.

# Configure Device A. The configuration on Device B is the same as that on Device A.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceA

[*HUAWEI] commit

[~DeviceA] interface Eth-Trunk 1

[*DeviceA-Eth-Trunk1] commit

[~DeviceA-Eth-Trunk1] quit

[~DeviceA] interface gigabitethernet0/3/0

[~DeviceA-Gigabitethernet0/3/0] undo shutdown

[*DeviceA-Gigabitethernet0/3/0] eth-trunk 1

[*DeviceA-Gigabitethernet0/3/0] commit

[~DeviceA-Gigabitethernet0/3/0] quit

[~DeviceA] interface gigabitethernet0/3/1

[~DeviceA-Gigabitethernet0/3/1] undo shutdown

[*DeviceA-Gigabitethernet0/3/1] eth-trunk 1

[*DeviceA-Gigabitethernet0/3/1] commit

[~DeviceA-Gigabitethernet0/3/1] quit

Assign IP addresses to the Eth-Trunk interfaces on Device A and Device B so that Device A and Device B can interwork with each other through the Eth-Trunk interfaces.

# Configure Device A. The configuration on Device B is the same as that on Device A.

[~DeviceA] interface Eth-Trunk 1

[~DeviceA-Eth-Trunk1] ip address 10.1.1.1 24

[*DeviceA-Eth-Trunk1] commit

[~DeviceA-Eth-Trunk1] quit

After the configuration is complete, the Eth-Trunk 1 interfaces on Device A and Device B can ping each other.

The following example uses the command output on Device B.

[~DeviceB] ping 10.1.1.1

  PING 10.1.1.1: 56  data bytes, press CTRL_C to break

    Reply from 10.1.1.1: bytes=56 Sequence=1 ttl=255 time=10 ms

    Reply from 10.1.1.1: bytes=56 Sequence=2 ttl=255 time=2 ms

    Reply from 10.1.1.1: bytes=56 Sequence=3 ttl=255 time=2 ms

    Reply from 10.1.1.1: bytes=56 Sequence=4 ttl=255 time=1 ms

    Reply from 10.1.1.1: bytes=56 Sequence=5 ttl=255 time=2 ms

  --- 10.1.1.1 ping statistics ---

    5 packet(s) transmitted

    5 packet(s) received

    0.00% packet loss

    round-trip min/avg/max = 1/3/10 ms

Configure a BFD for link-bundle session on Device A and Device B to monitor the Eth-Trunk member links between Device A and Device B.

# Configure Device A.

[~DeviceA] bfd

[*DeviceA-bfd] quit

[*DeviceA] bfd atob bind link-bundle peer-ip 10.1.1.2 interface Eth-Trunk 1 source-ip 10.1.1.1

[*DeviceA-bfd-session-atob] min-rx-interval 10

[*DeviceA-bfd-session-atob] min-tx-interval 10

[*DeviceA-bfd-session-atob] commit

[~DeviceA-bfd-session-atob] quit

# Configure Device B.

[~DeviceB] bfd

[*DeviceB-bfd] quit

[*DeviceB] bfd btoa bind link-bundle peer-ip 10.1.1.1 interface Eth-Trunk 1 source-ip 10.1.1.2

[*DeviceB-bfd-session-btoa] min-rx-interval 10

[*DeviceB-bfd-session-btoa] min-tx-interval 10

[*DeviceB-bfd-session-btoa] commit

[~DeviceB-bfd-session-btoa] quit

Verify the configuration.

After completing the configuration, run the display bfd link-bundle session command on Device A. The command output shows that three BFD sessions have been established and their statuses are Up. The discriminators of the three BFD sessions are dynamically allocated by the system. The BFD session bound to Eth-Trunk 1 is the main session, and the other two are BFD sub-sessions and bound to GE 0/3/0 and GE 0/3/1.

<DeviceA> display bfd link-bundle session

Total Up/Down Main Session Number : 1/0
Total Up/Down Sub Session Number : 2/0
--------------------------------------------------------------------------------
  Name                   : a 
  State                  : Up  
  Local Discriminator    : 1048576 
  Remote Discriminator   : -                   
  Session Detect Mode    : Asynchronous Mode Without Echo Function              
  BFD Bind Type          : Interface(Eth-Trunk1)                                
  Bind Session Type      : Static_Auto(Bundle_Main | Compatible)
  Bind Peer IP Address   : 10.1.1.2                                              
  Bind Source IP Address : 10.1.1.1                                              
  FSM Board Id           : -                
  TOS-EXP                : 7          
  Min Tx Interval (ms)   : 10               
  Min Rx Interval (ms)   : 10   
  Local Detect Multi     : 3      
  WTR Interval (ms)      : -                                                                    
  Last Local Diagnostic  : Control Detection Time Expired                                        
  Bind Application       : AUTO 
  Sub Session Count      : 2
--------------------------------------------------------------------------------
      Sub Session Number     : 1
      State                  : Up
      Local Discriminator    : 16385 
      Remote Discriminator   : 16385                   
      BFD Bind Type          : Interface(GigabitEthernet0/3/0)                                
      Bind Session Type      : Dynamic(Bundle_Sub | Compatible)
      FSM Board Id           : 9                
      Min Tx Interval (ms)   : 10               
      Min Rx Interval (ms)   : 10   
      Local Detect Multi     : 3      
      Actual Tx Interval (ms): 10               
      Actual Rx Interval (ms): 10  
      Active Multi           : 3                      
      Detect Interval (ms)   : 30                    
      Destination Port       : 3784
      Last Local Diagnostic  : Control Detection Time Expired                              
--------------------------------------------------------------------------------
      Sub Session Number     : 2
      State                  : Up
      Local Discriminator    : 16386 
      Remote Discriminator   : 16386                   
      BFD Bind Type          : Interface(GigabitEthernet0/3/1)                                
      Bind Session Type      : Dynamic(Bundle_Sub | Compatible)
      FSM Board Id           : 9                
      Min Tx Interval (ms)   : 10               
      Min Rx Interval (ms)   : 10   
      Local Detect Multi     : 3      
      Actual Tx Interval (ms): 10               
      Actual Rx Interval (ms): 10  
      Active Multi           : 3                      
      Detect Interval (ms)   : 30                    
      Destination Port       : 3784
      Last Local Diagnostic  : Control Detection Time Expired                                  
--------------------------------------------------------------------------------

# Shut down GE 0/3/0 on Device A.

[~DeviceA] interface gigabitethernet0/3/0

[~DeviceA-Gigabitethernet0/3/0] shutdown

[*DeviceA-Gigabitethernet0/3/0] quit

# Run the display bfd session all command on Device A to view the statuses of the BFD sessions. The command output shows that the status of the BFD sub-session bound to GE 0/3/0 is Down and that the status of the main session bound to Eth-Trunk 1 is still Up.

<DeviceA> display bfd session all

S: Static session
D: Dynamic session
IP: IP session
IF: Single-hop session
PEER: Multi-hop session
AUTO: Automatically negotiated session
(w): State in WTR 
(*): State is invalid
Total UP/DOWN Session Number : 2/1
--------------------------------------------------------------------------------
Local      Remote     PeerIpAddr      State     Type        InterfaceName 
--------------------------------------------------------------------------------
1048576    -          10.1.1.2       Up        S/AUTO-IF   Eth-Trunk1
16386      0          10.1.1.2       Down      D/IP-IF     Gigabitethernet0/3/0
16387      16387      10.1.1.2       Up        D/IP-IF     Gigabitethernet0/3/1
--------------------------------------------------------------------------------

# Shut down GE 0/3/1, and run the display bfd session all command on Device A. The command output shows that the statuses of the BFD sessions are all Down.

<DeviceA> display bfd session all

S: Static session
D: Dynamic session
IP: IP session
IF: Single-hop session
PEER: Multi-hop session
AUTO: Automatically negotiated session
(w): State in WTR 
(*): State is invalid
Total UP/DOWN Session Number : 0/3
--------------------------------------------------------------------------------
Local      Remote     PeerIpAddr      State     Type        InterfaceName 
--------------------------------------------------------------------------------
1048576    -          10.1.1.2       Down      S/AUTO-IF   Eth-Trunk1
16386      0          10.1.1.2       Down      D/IP-IF     Gigabitethernet0/3/0
16387      0          10.1.1.2       Down      D/IP-IF     Gigabitethernet0/3/1
--------------------------------------------------------------------------------

Configuration Files

Device A configuration file

 sysname DeviceA

bfd

interface Eth-Trunk1

 ip address 10.1.1.1 255.255.255.0

interface Gigabitethernet0/3/0

 undo shutdown

 eth-trunk 1

interface Gigabitethernet0/3/1

 undo shutdown

 eth-trunk 1

bfd atob bind link-bundle peer-ip 10.1.1.2 interface Eth-Trunk1 source-ip 10.1.1.1

 min-tx-interval 10

 min-rx-interval 10

return

Device B configuration file

 sysname DeviceB

bfd

interface Eth-Trunk1

 ip address 10.1.1.2 255.255.255.0

interface Gigabitethernet0/3/0

 undo shutdown

 eth-trunk 1

interface Gigabitethernet0/3/1

 undo shutdown

 eth-trunk 1

bfd btoa bind link-bundle peer-ip 10.1.1.1 interface Eth-Trunk1 source-ip 10.1.1.2

 min-tx-interval 10

 min-rx-interval 10

return

Example for Configuring a BFD for Link-Bundle Session to Detect Layer 3 Eth-Trunk Member Link Faults (IPv6)

This section provides an example for configuring a BFD for link-bundle session to monitor Layer 3 Eth-Trunk member links and rapidly detect link faults in an IPv6 scenario.

Networking Requirements

On the network shown in Figure 3-14, DeviceA and DeviceB are directly connected through Layer 3 Eth-Trunk interfaces. BFD sessions can be bound to Eth-Trunk interfaces to detect the connectivity of the Eth-Trunk between DeviceA and DeviceB. If single-hop BFD sessions are used, BFD selects one of the Eth-Trunk member links to monitor the state of the Eth-Trunk. Once BFD detects that the selected member link is down, it assumes the Eth-Trunk is down even if the other member links of the Eth-Trunk are up. To prevent BFD from incorrectly identifying the Eth-Trunk state, deploy BFD for link-bundle sessions instead of single-hop BFD sessions.

Figure 3-14 Configuring a BFD for link-bundle session to detect Eth-Trunk member link faults (IPv6)

Interfaces 1 and 2 in this example represent GE 0/3/0 and GE 0/3/1, respectively.

Configuration Roadmap

The configuration roadmap is as follows:

Create an Eth-Trunk interface on DeviceA and DeviceB, and then add Ethernet physical interfaces to each Eth-Trunk interface.
Assign IPv6 addresses to the Eth-Trunk interfaces on DeviceA and DeviceB to enable the devices to interwork with each other through the Eth-Trunk interfaces.
Configure a BFD for link-bundle session on DeviceA and DeviceB to monitor the Eth-Trunk member links between them.

The IPv6 addresses configured for Eth-Trunk interfaces can be global or link-local addresses. If global addresses are used, BFD for link-bundle cannot share a session with BFD for IGP. However, if link-local addresses are used, BFD for link-bundle can share a session with BFD for IGP. In this example, global addresses are used.

Data Preparation

To complete the configuration, you need the following data:

IDs of the physical interfaces connecting DeviceA and DeviceB
IPv6 addresses of the Eth-Trunk interfaces
The minimum interval at which BFD for link-bundle session packets are received

Procedure

Create an Eth-Trunk interface on DeviceA and DeviceB, and then add Ethernet physical interfaces to each Eth-Trunk interface.

# Configure DeviceA. The configuration of DeviceB is similar to the configuration of DeviceA. For configuration details, see Configuration Files in this section.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceA

[*HUAWEI] commit

[~DeviceA] interface Eth-Trunk 1

[*DeviceA-Eth-Trunk1] commit

[~DeviceA-Eth-Trunk1] quit

[~DeviceA] interface gigabitethernet0/3/0

[~DeviceA-Gigabitethernet0/3/0] undo shutdown

[*DeviceA-Gigabitethernet0/3/0] eth-trunk 1

[*DeviceA-Gigabitethernet0/3/0] commit

[~DeviceA-Gigabitethernet0/3/0] quit

[~DeviceA] interface gigabitethernet0/3/1

[~DeviceA-Gigabitethernet0/3/1] undo shutdown

[*DeviceA-Gigabitethernet0/3/1] eth-trunk 1

[*DeviceA-Gigabitethernet0/3/1] commit

[~DeviceA-Gigabitethernet0/3/1] quit

Assign IPv6 addresses to the Eth-Trunk interfaces on DeviceA and DeviceB to enable the devices to interwork with each other through the Eth-Trunk interfaces.

# Configure DeviceA. The configuration of DeviceB is similar to the configuration of DeviceA. For configuration details, see Configuration Files in this section.

[~DeviceA] interface Eth-Trunk 1

[~DeviceA-Eth-Trunk1] ipv6 enable

[~DeviceA-Eth-Trunk1] ipv6 address 2001:DB8:1::1 64

[*DeviceA-Eth-Trunk1] commit

[~DeviceA-Eth-Trunk1] quit

After the configuration is complete, Eth-Trunk 1 on DeviceA and DeviceB can ping each other.

The following example uses the command output on DeviceB.

[~DeviceB] ping ipv6 2001:DB8:1::1

  PING 2001:DB8:1::1 56  data bytes, press CTRL_C to break

    Reply from 2001:DB8:1::1: bytes=56 Sequence=1 ttl=255 time=10 ms

    Reply from 2001:DB8:1::1: bytes=56 Sequence=2 ttl=255 time=2 ms

    Reply from 2001:DB8:1::1: bytes=56 Sequence=3 ttl=255 time=2 ms

    Reply from 2001:DB8:1::1: bytes=56 Sequence=4 ttl=255 time=1 ms

    Reply from 2001:DB8:1::1: bytes=56 Sequence=5 ttl=255 time=2 ms

  --- 2001:DB8:1::1 ping statistics ---

    5 packet(s) transmitted

    5 packet(s) received

    0.00% packet loss

    round-trip min/avg/max = 1/3/10 ms

Configure a BFD for link-bundle session on DeviceA and DeviceB to monitor the Eth-Trunk member links between them.

# Configure DeviceA.

[~DeviceA] bfd

[*DeviceA-bfd] quit

[*DeviceA] bfd atob bind link-bundle peer-ipv6 2001:DB8:1::2 interface Eth-Trunk 1 source-ipv6 2001:DB8:1::1

[*DeviceA-bfd-session-atob] min-rx-interval 10

[*DeviceA-bfd-session-atob] min-tx-interval 10

[*DeviceA-bfd-session-atob] commit

[~DeviceA-bfd-session-atob] quit

# Configure DeviceB.

[~DeviceB] bfd

[*DeviceB-bfd] quit

[*DeviceB] bfd btoa bind link-bundle peer-ipv6 2001:DB8:1::1 interface Eth-Trunk 1 source-ipv6 2001:DB8:1::2

[*DeviceB-bfd-session-btoa] min-rx-interval 10

[*DeviceB-bfd-session-btoa] min-tx-interval 10

[*DeviceB-bfd-session-btoa] commit

[~DeviceB-bfd-session-btoa] quit

Verify the configuration.

# After completing the configuration, run the display bfd link-bundle session command on DeviceA. The command output shows that three BFD sessions have been established and are in the Up state. The discriminators of the three BFD sessions are dynamically allocated by the system. The BFD session bound to Eth-Trunk 1 is the main session, and the other two are BFD sub-sessions bound to GE 0/3/0 and GE 0/3/1, respectively.

[DeviceA] display bfd link-bundle session

Total Up/Down Main Session Number : 1/0
Total Up/Down Sub Session Number : 2/0
--------------------------------------------------------------------------------
  Name                   : atob 
  State                  : Up  
  Local Discriminator    : 1048576 
  Remote Discriminator   : -                   
  Session Detect Mode    : Asynchronous Mode Without Echo Function              
  BFD Bind Type          : Interface(Eth-Trunk1)                                
  Bind Session Type      : Static_Auto(Bundle_Main | Compatible)
  Bind Peer IP Address   : 2001:DB8:1::2                                              
  Bind Source IP Address : 2001:DB8:1::1                                              
  FSM Board Id           : -                
  TOS-EXP                : 7          
  Min Tx Interval (ms)   : 10               
  Min Rx Interval (ms)   : 10   
  Local Detect Multi     : 3      
  WTR Interval (ms)      : -                                                                    
  Last Local Diagnostic  : Control Detection Time Expired                                        
  Bind Application       : AUTO 
  Sub Session Count      : 2
--------------------------------------------------------------------------------
      Sub Session Number     : 1
      State                  : Up
      Local Discriminator    : 16385 
      Remote Discriminator   : 16385                   
      BFD Bind Type          : Interface(GigabitEthernet0/3/0)                                
      Bind Session Type      : Dynamic(Bundle_Sub | Compatible)
      FSM Board Id           : 9                
      Min Tx Interval (ms)   : 10               
      Min Rx Interval (ms)   : 10   
      Local Detect Multi     : 3      
      Actual Tx Interval (ms): 10               
      Actual Rx Interval (ms): 10  
      Active Multi           : 3                      
      Detect Interval (ms)   : 30                    
      Destination Port       : 6784
      Last Local Diagnostic  : Control Detection Time Expired                              
--------------------------------------------------------------------------------
      Sub Session Number     : 2
      State                  : Up
      Local Discriminator    : 16386 
      Remote Discriminator   : 16386                   
      BFD Bind Type          : Interface(GigabitEthernet0/3/1)                                
      Bind Session Type      : Dynamic(Bundle_Sub | Compatible)
      FSM Board Id           : 9                
      Min Tx Interval (ms)   : 10               
      Min Rx Interval (ms)   : 10   
      Local Detect Multi     : 3      
      Actual Tx Interval (ms): 10               
      Actual Rx Interval (ms): 10  
      Active Multi           : 3                      
      Detect Interval (ms)   : 30                    
      Destination Port       : 3784
      Last Local Diagnostic  : Control Detection Time Expired                                  
--------------------------------------------------------------------------------

# Shut down GE 0/3/0 on DeviceA.

[~DeviceA] interface gigabitethernet0/3/0

[~DeviceA-Gigabitethernet0/3/0] shutdown

[*A-Gigabitethernet0/3/0] commit

[~DeviceA-Gigabitethernet0/3/0] quit

# Run the display bfd session all command on DeviceA to view the states of the BFD sessions. The command output shows that the BFD sub-session bound to GE 0/3/0 is in the Down state and the BFD main session bound to Eth-Trunk 1 is still in the Up state.

[DeviceA] display bfd session all

S: Static session
D: Dynamic session
IP: IP session
IF: Single-hop session
PEER: Multi-hop session
AUTO: Automatically negotiated session
(w): State in WTR  (*): State is invalid
Total UP/DOWN Session Number : 2/1
--------------------------------------------------------------------------------
Local      Remote     PeerIpAddr      State     Type        InterfaceName 
--------------------------------------------------------------------------------
1048576    -          2001:DB8:1::1       Up        S/AUTO-IF   Eth-Trunk1
16386      0          2001:DB8:1::1       Down      D/IP-IF     Gigabitethernet0/3/0
16387      16387      2001:DB8:1::1       Up        D/IP-IF     Gigabitethernet0/3/1
--------------------------------------------------------------------------------

# Shut down GE 0/3/1, and run the display bfd session all command on DeviceA. The command output shows that all three BFD sessions are in the Down state.

[DeviceA] display bfd session all

S: Static session
D: Dynamic session
IP: IP session
IF: Single-hop session
PEER: Multi-hop session
AUTO: Automatically negotiated session
(w): State in WTR  (*): State is invalid
Total UP/DOWN Session Number : 0/3
--------------------------------------------------------------------------------
Local      Remote     PeerIpAddr      State     Type        InterfaceName 
--------------------------------------------------------------------------------
1048576               2001:DB8:1::2       Down      D/AUTO-IF   Eth-Trunk1
16386      0          2001:DB8:1::2       Down      D/IP-IF     Gigabitethernet0/3/0
16387      -          2001:DB8:1::2       Down      A/IP-IF     Gigabitethernet0/3/1
--------------------------------------------------------------------------------

Configuration Files

DeviceA configuration file

 sysname DeviceA

interface Eth-Trunk1

 ipv6 enable

 ipv6 address 2001:DB8:1::1 64

interface Gigabitethernet0/3/0

 undo shutdown

 eth-trunk 1

interface Gigabitethernet0/3/1

 undo shutdown

 eth-trunk 1

bfd

bfd atob bind link-bundle peer-ipv6 2001:DB8:1::2 interface Eth-Trunk1 source-ipv6 2001:DB8:1::1

 min-tx-interval 10

 min-rx-interval 10

return

DeviceB configuration file

 sysname DeviceB

interface Eth-Trunk1

 ipv6 enable

 ipv6 address 2001:DB8:1::2 64

interface Gigabitethernet0/3/0

 undo shutdown

 eth-trunk 1

interface Gigabitethernet0/3/1

 undo shutdown

 eth-trunk 1

bfd

bfd btoa bind link-bundle peer-ipv6 2001:DB8:1::1 interface Eth-Trunk1 source-ipv6 2001:DB8:1::2

 min-tx-interval 10

 min-rx-interval 10

return

Example for Configuring a One-Arm BFD Echo Session

This section provides an example for configuring a one-arm BFD echo session on a device that supports BFD.

Networking Requirements

As shown in Figure 3-15, Device A supports BFD, whereas Device B does not. To rapidly detect faults in the direct link between Device A and Device B, configure a one-arm BFD echo session on Device A. After receiving a one-arm BFD echo session packet from Device A, Device B immediately loops back the packet, implementing rapid link fault detection.

Figure 3-15 Configuring a one-arm BFD echo session

Interfaces 1 in this example are GE 0/1/0.

Configuration Roadmap

The configuration roadmap is as follows:

Assign IP addresses to the interfaces through which Device A and Device B are directly connected.
Configure a one-arm BFD echo session on Device A.

Data Preparation

To complete the configuration, you need the following data:

Peer IP address monitored by a one-arm BFD echo session
Local discriminator of a one-arm BFD echo session
Minimum interval at which one-arm BFD echo session packets are received

Procedure

Assign IP addresses to the interfaces through which Device A and Device B are directly connected.

# Assign an IP address to Device A's interface through which Device A is directly connected to Device B.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceA

[*HUAWEI] commit

[~DeviceA] interface gigabitethernet 0/1/0

[~DeviceA-GigabitEthernet0/1/0] undo shutdown

[*DeviceA-GigabitEthernet0/1/0] ip address 10.1.1.1 24

[*DeviceA-GigabitEthernet0/1/0] commit

[~DeviceA-GigabitEthernet0/1/0] quit

# Assign an IP address to Device B's interface through which Device B is directly connected to Device A.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceB

[*HUAWEI] commit

[~DeviceB] interface gigabitethernet 0/1/0

[~DeviceB-GigabitEthernet0/1/0] undo shutdown

[*DeviceB-GigabitEthernet0/1/0] ip address 10.1.1.2 24

[*DeviceB-GigabitEthernet0/1/0] commit

[~DeviceB-GigabitEthernet0/1/0] quit

Configure a one-arm BFD echo session on Device A.

# Configure Device A.

[~DeviceA] bfd

[*DeviceA-bfd] quit

[*DeviceA] bfd atob bind peer-ip 10.1.1.2 interface gigabitEthernet0/1/0 one-arm-echo

[*DeviceA-bfd-session-atob] discriminator local 1

[*DeviceA-bfd-session-atob] min-echo-rx-interval 100

[*DeviceA-bfd-session-atob] commit

[~DeviceA-bfd-session-atob] quit

[~DeviceA] quit

Verify the configuration.

After completing the configuration, run the display bfd session all verbose command on Device A. The command output shows that a one-arm BFD echo session has been established and its status is Up.

<DeviceA> display bfd session all verbose

(w): State in WTR  (*): State is invalid
--------------------------------------------------------------------------------
  (One Hop)   State : Up                  Name : atob
--------------------------------------------------------------------------------
  Local Discriminator    : 1                Remote Discriminator   : -
  Session Detect Mode    : Asynchronous One-arm-echo Mode
  BFD Bind Type          : Interface(gigabitEthernet0/1/0)
  Bind Session Type      : Static 
  Bind Peer IP Address   : 10.1.1.2         
  Bind Interface         : GigabitEthernet0/1/0
  Track Interface        : -  
  FSM Board Id           : 10               TOS-EXP                : 7
  Echo Rx Interval (ms)  : 100 
  Actual Tx Interval (ms): 100              Actual Rx Interval (ms): 100 
  Local Detect Multi     : 3                Detect Interval (ms)   : 300 
  Echo Passive           : Disable          Acl Number             : - 
  Destination Port       : 3784             TTL                    : 255 
  Proc Interface Status  : Disable          Process PST            : Disable    
  WTR Interval (ms)      : -                Config PST             : Disable    
  Active Multi           : 3                  
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : -                Session Detect TmrID   : - 
  Session Init TmrID     : -                Session WTR TmrID      : - 
  Session Echo Tx TmrID  : -   
  Session Not Up Reason  : -  
050928
  Session Description    : - 
--------------------------------------------------------------------------------

       Total UP/DOWN Session Number : 1/0

Configuration Files

Device A configuration file

 sysname DeviceA

bfd

interface gigabitethernet0/1/0

 undo shutdown

 ip address 10.1.1.1 255.255.255.0

bfd atob bind peer-ip 10.1.1.2 interface gigabitEthernet0/1/0 one-arm-echo

 discriminator local 1

 min-echo-rx-interval 100

 commit

return

Device B configuration file

 sysname DeviceB

interface gigabitethernet0/1/0

 undo shutdown

 ip address 10.1.1.2 255.255.255.0

return

Example for Configuring the Delay of a BFD Session to Go Up

This section provides an example for configuring the delay of a BFD session to go Up. This configuration prevents traffic loss because a routing protocol goes Up later than an interface.

Networking Requirements

Some devices switch traffic according to whether a BFD session is Up. When a routing protocol goes Up later than an interface, no route can be found during traffic switchbacks. As a result, traffic is discarded. To resolve this issue, configure a delay to compensate for the time difference caused when the routing protocol goes Up later than the interface.

As shown in Figure 3-16, BFD in asynchronous mode is used to monitor the direct link between Device A and Device B.

Figure 3-16 Configuring the delay of a BFD session to go Up

Interfaces 1 in this example are GE 0/1/0.

Configuration Roadmap

The configuration roadmap is as follows:

Configure a BFD session on Device A to monitor the direct link from Device A to Device B.
Configure a BFD session on Device B to monitor the direct link from Device B to Device A.

Precautions

None

Data Preparation

To complete the configuration, you need the following data:

Peer IP address monitored by BFD
IP address of a local interface that sends and receives BFD control packets
BFD session names
Local and remote discriminators of BFD sessions
Delay of the BFD session to go Up

Procedure

Assign IP addresses to the interfaces connecting Device A and Device B.

# Assign an IP address to the interface on Device A.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceA

[*HUAWEI] commit

[~DeviceA] interface gigabitethernet 0/1/0

[~DeviceA-GigabitEthernet0/1/0] undo shutdown

[*DeviceA-GigabitEthernet0/1/0] ip address 10.1.1.1 24

[*DeviceA-GigabitEthernet0/1/0] commit

[~DeviceA-GigabitEthernet0/1/0] quit

# Assign an IP address to the interface on Device B.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceB

[*HUAWEI] commit

[~DeviceB] interface gigabitethernet 0/1/0

[~DeviceB-GigabitEthernet0/1/0] undo shutdown

[*DeviceB-GigabitEthernet0/1/0] ip address 10.1.1.2 24

[*DeviceB-GigabitEthernet0/1/0] commit

[~DeviceB-GigabitEthernet0/1/0] quit

Configure the delay of the BFD session to go Up.

# Enable BFD on Device A and set the delay of the BFD session to go Up to 120s in the BFD view.

To configure the delay of a BFD session to go Up, run the delay-up command only in the BFD view. This command takes effect only for BFD sessions to be established.

[~DeviceA] bfd

[*DeviceA-bfd] delay-up 120

[*DeviceA-bfd] commit

[~DeviceA-bfd] quit

# Configure BFD on Device A. The following example uses the configuration of single-hop BFD.

[~DeviceA] bfd atob bind peer-ip 10.1.1.2 interface gigabitethernet 0/1/0

[*DeviceA-bfd-session-atob] discriminator local 10

[*DeviceA-bfd-session-atob] discriminator remote 20

[*DeviceA-bfd-session-atob] commit

[~DeviceA-bfd-session-atob] quit

# Enable BFD on Device B and set the delay of the BFD session to go Up to 120s in the BFD view.

[~DeviceB]bfd

[*DeviceB-bfd] delay-up 120

[*DeviceB-bfd] commit

[~DeviceB-bfd] quit

# Configure BFD on Device B. The following example uses the configuration of single-hop BFD.

[~DeviceB] bfd btoa bind peer-ip 10.1.1.1 interface gigabitethernet 0/1/0

[*DeviceB-bfd-session-btoa] discriminator local 10

[*DeviceB-bfd-session-btoa] discriminator remote 20

[*DeviceB-bfd-session-btoa] commit

[~DeviceB-bfd-session-btoa] quit

Verify the configuration.

After completing the configurations, run the display bfd statistics command on Device A and Device B. The command output shows that System Session Delay Up Timer is 120, indicating that the BFD session goes Up after a delay of 120s.

The following example uses the command output on Device A.

[~DeviceA] display bfd statistics

Current Display Board Number : Main ; Current Product Register Type:
Total Up/Down Session Number : 1/0
Current Session Number :
      Static session     : 1                Dynamic session        : 0
      E_Dynamic session  : 0                STATIC_AUTO session    : 0
      LDP_LSP session    : 0                STATIC_LSP session     : 0
      TE_TUNNEL session  : 0                TE_LSP session         : 0
      PW session         : 0                IP session             : 1
      VSI PW session     : 0
------------------------------------------------------------------------------
PAF/LCS Name                       Maxnum         Minnum         Create
------------------------------------------------------------------------------
BFD_CFG_NUM                        16384          1              1
BFD_IO_SESSION_NUM                 2048           1              0
BFD_PER_TUNNEL_CFG_NUM             16             1              0
------------------------------------------------------------------------------
Current Total Used Discriminator Num               : 1
------------------------------------------------------------------------------
BFD HAF Information :
------------------------------------------------------------------------------
Current HAF Status                                 : Work
------------------------------------------------------------------------------
BFD for LSP Information :
------------------------------------------------------------------------------
Ability of auto creating BFD session on egress     : Disable
Period of LSP Ping                                 : 60
------------------------------------------------------------------------------
BFD other Information :
------------------------------------------------------------------------------
System Session Delay Up Timer                       : 120
------------------------------------------------------------------------------

Configuration Files

Device A configuration file

 sysname DeviceA

bfd

 delay-up 120

interface gigabitethernet0/1/0

 undo shutdown

 ip address 10.1.1.1 255.255.255.0

bfd atob bind peer-ip 10.1.1.2 interface gigabitethernet 0/1/0

 discriminator local 10

 discriminator remote 20

return

Device B configuration file

 sysname DeviceB

bfd

 delay-up 120

interface gigabitethernet0/1/0

 undo shutdown

 ip address 10.1.1.2 255.255.255.0

bfd btoa bind peer-ip 10.1.1.1 interface gigabitethernet 0/1/0

 discriminator local 20

 discriminator remote 10

return

Example for Associating a BFD Session with an Interface

This section provides an example for associating a BFD session with an interface to trigger rapid route convergence if a fault occurs.

Networking Requirements

On the network shown in Figure 3-17, transmission devices exist on the link between Device A and Device B. A BFD session is associated with an interface on the Devices. If the link between GE 0/1/0 on Device A and GE 0/1/0 on Device B fails, associate a BFD session with an interface to detect the fault. The BFD session status change affects the interface protocol status change, triggering rapid route convergence.

Figure 3-17 Association between a BFD session and an interface

Interfaces 1 in this example are GE 0/1/0.

Configuration Roadmap

The configuration roadmap is as follows:

Configure a BFD session on Device A.
Configure a BFD session on Device B.
Associate the BFD session and an interface on Device A.
Associate the BFD session and an interface on Device B.

Precautions

BFD sessions must be established on both ends.

Data Preparation

To complete the configuration, you need the following data:

Peer IP address monitored by BFD
IP address of a local interface that sends and receives BFD control packets
Local and remote discriminators of BFD sessions

Procedure

Assign IP addresses to the interfaces connecting Device A and Device B.

# Assign an IP address to the interface on Device A.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceA

[*HUAWEI] commit

[~DeviceA] interface gigabitethernet 0/1/0

[~DeviceA-GigabitEthernet0/1/0] undo shutdown

[*DeviceA-GigabitEthernet0/1/0] ip address 10.1.1.1 24

[*DeviceA-GigabitEthernet0/1/0] commit

[~DeviceA-GigabitEthernet0/1/0] quit

# Assign an IP address to the interface on Device B.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceB

[*HUAWEI] commit

[~DeviceB] interface gigabitethernet 0/1/0

[~DeviceB-GigabitEthernet0/1/0] undo shutdown

[*DeviceB-GigabitEthernet0/1/0] ip address 10.1.1.2 24

[*DeviceB-GigabitEthernet0/1/0] commit

[~DeviceB-GigabitEthernet0/1/0] quit

After the configuration is complete, Device A and Device B can ping each other. The following example uses the command output on Device A.

[~DeviceA] ping 10.1.1.2

PING 10.1.1.2 : 56  data bytes, press CTRL_C to break
    Reply from 10.1.1.2: bytes=56 Sequence=1 ttl=255 time=3 ms
    Reply from 10.1.1.2: bytes=56 Sequence=2 ttl=255 time=1 ms
    Reply from 10.1.1.2: bytes=56 Sequence=3 ttl=255 time=1 ms
    Reply from 10.1.1.2: bytes=56 Sequence=4 ttl=255 time=1 ms
    Reply from 10.1.1.2: bytes=56 Sequence=5 ttl=255 time=1 ms

  --- 10.1.1.2 ping statistics ---
    5 packet(s) transmitted
    5 packet(s) received
    0.00% packet loss
    round-trip min/avg/max = 1/1/3 ms

Configure single-hop BFD.

# Enable BFD on Device A, and configure a BFD session with Device B.

[~DeviceA] bfd

[*DeviceA-bfd] quit

[*DeviceA] bfd pis bind peer-ip default-ip interface gigabitethernet 0/1/0

[*DeviceA-bfd-session-pis] discriminator local 1

[*DeviceA-bfd-session-pis] discriminator remote 2

[*DeviceA-bfd-session-pis] commit

[~DeviceA-bfd-session-pis] quit

# Enable BFD on Device B, and configure a BFD session with Device A.

[~DeviceB] bfd

[*DeviceB-bfd] quit

[*DeviceB] bfd pis bind peer-ip default-ip interface gigabitethernet 0/1/0

[*DeviceB-bfd-session-pis] discriminator local 2

[*DeviceB-bfd-session-pis] discriminator remote 1

[*DeviceB-bfd-session-pis] commit

[~DeviceB-bfd-session-pis] quit

After completing the preceding configurations, run the display bfd session all verbose command on Device A or Device B. The command output shows that a single-hop BFD session has been established and its status is Up. The following example uses the command output Device A.

[~DeviceA] display bfd session all verbose

(w): State in WTR  (*): State is invalid
------------------------------------------------------------------------------
  (One Hop)   State : Up                    Name : pis
------------------------------------------------------------------------------
  Local Discriminator    : 1                Remote Discriminator   : 2
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(GigabitEthernet0/1/0)
  Bind Session Type      : Static
  Bind Peer IP Address   : 224.0.0.184
  Bind Interface         : GigabitEthernet0/1/0
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : 0                Session Detect TmrID   : 0
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 1/0

Associate the BFD sessions with the interfaces.

# Configure Device A.

[~DeviceA] bfd pis

[*DeviceA-bfd-session-pis] process-interface-status

[*DeviceA-bfd-session-pis] commit

[~DeviceA-bfd-session-pis] quit

# Configure Device B.

[~DeviceB] bfd pis

[*DeviceB-bfd-session-pis] process-interface-status

[*DeviceB-bfd-session-pis] commit

[~DeviceB-bfd-session-pis] quit

Verify the configuration.

After completing the configuration, run the display bfd session all verbose command on Device A or Device B. The command output shows that Proc Interface Status is Enable. The following example uses the command output on Device A.

[~DeviceA] display bfd session all verbose

(w): State in WTR  (*): State is invalid
------------------------------------------------------------------------------
  (One Hop)   State : Up                    Name : pis
------------------------------------------------------------------------------
  Local Discriminator    : 1                Remote Discriminator   : 2
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(GigabitEthernet0/1/0)
  Bind Session Type      : Static
  Bind Peer IP Address   : 224.0.0.184
  Bind Interface         : GigabitEthernet0/1/0
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255
  Proc Interface Status  : Enable       Process PST            : Disable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : 0                Session Detect TmrID   : 0
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 1/0

Run the shutdown command on GE 0/1/0 of Device B.

[~DeviceB] interface gigabitethernet 0/1/0

[~DeviceB-GigabitEthernet0/1/0] shutdown

[*DeviceB-GigabitEthernet0/1/0] commit

[~DeviceB-GigabitEthernet0/1/0] quit

Run the display bfd session all verbose and display interface commands on Device A. The command output shows that the BFD session is Down and GE 0/1/0 is Up.

[~DeviceA] display bfd session all verbose

(w): State in WTR  (*): State is invalid
------------------------------------------------------------------------------
  (One Hop)   State : Down                  Name : pis
------------------------------------------------------------------------------
  Local Discriminator    : 1                Remote Discriminator   : 2
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(GigabitEthernet0/1/0)
  Bind Session Type      : Static
  Bind Peer IP Address   : 224.0.0.184
  Bind Interface         : GigabitEthernet0/1/0
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 2100             Actual Rx Interval (ms): 2100
  Local Detect Multi     : 3                Detect Interval (ms)   : 0
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255
  Proc Interface Status  : Enable           Process PST            : Disable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : Control Detection Time Expired
  Bind Application       : No Application Bind
  Session TX TmrID       : 2725402068       Session Detect TmrID   : -
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 0/1

[~DeviceA] display interface gigabitethernet 0/1/0

GigabitEthernet0/1/0 current state : UP (ifindex: 20)
Line protocol current state : DOWN (BFD status down)  
EDescription: HUAWEI, Quidway Series, GigabitEthernet0/1/0 Interface
Route Port,The Maximum Transmit Unit is 1500
Internet Address is 10.1.1.2/24
IP Sending Frames' Format is PKTFMT_ETHNT_2, Hardware address is 00e0-fc12-7890
Current BW: 100 Mbits
Last physical up time   : 2010-07-31 09:35:03
Last physical down time : 2010-08-03 02:58:22
Current system time: 2010-08-03 03:02:48
Statistics last cleared:never
    Last 300 seconds input rate 0 bits/sec, 4 packets/sec
    Last 300 seconds output rate 0 bits/sec, 4 packets/sec
    Input: 0 bytes, 662126 packets
    Output: 0 bytes, 661789 packets
    Input:
      Unicast: 662111 packets, Multicast: 12 packets
      Broadcast: 3 packets, JumboOctets: 0 packets
      CRC: 0 packets, Symbol: 0 packets
      Overrun: 0 packets, InRangeLength: 0 packets
      LongPacket: 0 packets, Jabber: 0 packets, Alignment: 0 packets
      Fragment: 0 packets, Undersized Frame: 0 packets
      RxPause: 0 packets
    Output:
      Unicast: 661784 packets, Multicast: 3 packets
      Broadcast: 2 packets, JumboOctets: 0 packets
      Lost: 0 packets, Overflow: 0 packets, Underrun: 0 packets
      System: 0 packets, Overruns: 0 packets
      TxPause: 0 packets
    Last 300 seconds input utility rate:  0.00%
    Last 300 seconds output utility rate: 0.00%

Configuration Files

Device A configuration file

#
 sysname DeviceA
#
 bfd
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 10.1.1.1 255.255.255.0
#
bfd pis bind peer-ip default-ip interface GigabitEthernet0/1/0
 discriminator local 1
 discriminator remote 2
 process-interface-status
return

Device B configuration file

#
 sysname DeviceB
#
 bfd
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 10.1.1.2 255.255.255.0
#
bfd pis bind peer-ip default-ip interface GigabitEthernet0/1/0
 discriminator local 2
 discriminator remote 1
 process-interface-status
return

Example for Associating a BFD Session and a Sub-interface

This section provides an example for associating a BFD session with a sub-interface to improve service reliability on the sub-interface.

Networking Requirements

On the large metro Ethernet network shown in Figure 3-18, large numbers of VLAN services are configured on an interface's sub-interface and high reliability is required. Establish a BFD session to monitor the interface's link continuity, and associate the BFD session with the sub-interface. This configuration improves service reliability on the sub-interface and saves BFD session resources.

Figure 3-18 Association between a BFD session and a sub-interface

Interface 1 in this example represents GE 0/1/0.

Configuration Roadmap

The configuration roadmap is as follows:

Configure a BFD session on Device A.
Configure a BFD session on Device B.
Associate the BFD session and a sub-interface on Device A.
Associate the BFD session and a sub-interface on Device B.

Precautions

BFD sessions must be established on both ends.

Data Preparation

To complete the configuration, you need the following data:

IP address of the peer interface on a link to be monitored by BFD
IP address of a local interface that sends and receives BFD control packets
Local and remote discriminators of BFD sessions

Procedure

Assign IP addresses to interfaces on Device A and Device B, and create sub-interfaces.

# Configure Device A.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceA

[*HUAWEI] commit

[~DeviceA] interface gigabitethernet 0/1/0

[~DeviceA-GigabitEthernet0/1/0] undo shutdown

[*DeviceA-GigabitEthernet0/1/0] ip address 10.1.1.1 24

[*DeviceA-GigabitEthernet0/1/0] quit

[*DeviceA] interface gigabitethernet 0/1/0.1

[*DeviceA-GigabitEthernet0/1/0.1] undo shutdown

[*DeviceA-GigabitEthernet0/1/0.1] ip address 10.2.1.1 24

[*DeviceA-GigabitEthernet0/1/0.1] commit

[~DeviceA-GigabitEthernet0/1/0.1] quit

# Configure Device B.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceB

[*HUAWEI] commit

[~DeviceB] interface gigabitethernet 0/1/0

[~DeviceB-GigabitEthernet0/1/0] undo shutdown

[*DeviceB-GigabitEthernet0/1/0] ip address 10.1.1.2 24

[*DeviceB-GigabitEthernet0/1/0] quit

[*DeviceB] interface gigabitethernet 0/1/0.1

[*DeviceB-GigabitEthernet0/1/0.1] undo shutdown

[*DeviceB-GigabitEthernet0/1/0.1] ip address 10.2.1.2 24

[*DeviceB-GigabitEthernet0/1/0.1] commit

[~DeviceB-GigabitEthernet0/1/0.1] quit

Configure single-hop BFD.

# Configure Device A.

[~DeviceA] bfd

[*DeviceA-bfd] quit

[*DeviceA] bfd pissub bind peer-ip default-ip interface gigabitethernet 0/1/0

[*DeviceA-bfd-session-pissub] discriminator local 1

[*DeviceA-bfd-session-pissub] discriminator remote 2

[*DeviceA-bfd-session-pissub] commit

[~DeviceA-bfd-session-pissub] quit

# Configure Device B.

[~DeviceB] bfd

[*DeviceB-bfd] quit

[*DeviceB] bfd pissub bind peer-ip default-ip interface gigabitethernet 0/1/0

[*DeviceB-bfd-session-pissub] discriminator local 2

[*DeviceB-bfd-session-pissub] discriminator remote 1

[*DeviceB-bfd-session-pissub] commit

[~DeviceB-bfd-session-pissub] quit

# After completing the configurations, run the display bfd session all verbose command on Device A or Device B. The command output shows that a single-hop BFD session has been established and its status is Up. The following example uses the command output on Device A.

[~DeviceA] display bfd session all verbose

(w): State in WTR  (*): State is invalid
------------------------------------------------------------------------------
  (One Hop)   State : Up                    Name : pissub
---------------------------------------------------------------------------
  Local Discriminator    : 1                Remote Discriminator   : 2
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(GigabitEthernet0/1/0)
  Bind Session Type      : Static
  Bind Peer IP Address   : 224.0.0.184
  Bind Interface         : GigabitEthernet0/1/0
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : 0                Session Detect TmrID   : 0
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 1/0

Associate the BFD sessions with the sub-interfaces.

# Configure Device A.

[~DeviceA] bfd pissub

[*DeviceA-bfd-session-pissub] process-interface-status sub-if

[*DeviceA-bfd-session-pissub] commit

[~DeviceA-bfd-session-pissub] quit

# Configure Device B.

[*DeviceB] bfd pissub

[*DeviceB-bfd-session-pissub] process-interface-status sub-if

[*DeviceB-bfd-session-pissub] commit

[~DeviceB-bfd-session-pissub] quit

Verify the configuration.

# After completing the configuration, run the display bfd session all verbose command on Device A or Device B. The command output shows that Proc Interface Status is Enable (Sub-If). The following example uses the command output on Device A.

[~DeviceA] display bfd session all verbose

(w): State in WTR  (*): State is invalid
------------------------------------------------------------------------------
  (One Hop)   State : Up                    Name : pissub
------------------------------------------------------------------------------
  Local Discriminator    : 1                Remote Discriminator   : 2
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(GigabitEthernet0/1/0)
  Bind Session Type      : Static
  Bind Peer IP Address   : 224.0.0.184
  Bind Interface         : GigabitEthernet0/1/0
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255
  Proc Interface Status  : Enable (Sub-If) Process PST            : Disable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : Control Detection Time Expired
  Bind Application       : No Application Bind
  Session TX TmrID       : 0                Session Detect TmrID   : 0
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 1/0

# Run the shutdown command on GE 0/1/0 of Device B.

[~DeviceB] interface gigabitethernet 0/1/0

[~DeviceB-GigabitEthernet0/1/0] shutdown

[*DeviceB-GigabitEthernet0/1/0] commit

[~DeviceB-GigabitEthernet0/1/0] quit

# Run the display bfd session all verbose and display interface commands on Device A. The command output shows that the BFD session is Down and GE 0/1/0.1 is Up.

[~DeviceA] display bfd session all verbose

(w): State in WTR  (*): State is invalid
------------------------------------------------------------------------------
  (One Hop)   State : Down                  Name : pissub
------------------------------------------------------------------------------
  Local Discriminator    : 1                Remote Discriminator   : 2
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(GigabitEthernet0/1/0)
  Bind Session Type      : Static
  Bind Peer IP Address   : 224.0.0.184
  Bind Interface         : GigabitEthernet0/1/0
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255
  Proc Interface Status  : Enable (Sub-If)  Process PST            : Disable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : Control Detection Time Expired
  Bind Application       : No Application Bind
  Session TX TmrID       : 0                Session Detect TmrID   : 0
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 0/1

[~DeviceA] display interface gigabitethernet 0/1/0.1

GigabitEthernet0/1/0.1 current state : DOWN (ifindex: 33)
Line protocol current state : DOWN (Main BFD status down)
Last line protocol up time :  2013-07-29 15:39:29
Description: HUAWEI, GigabitEthernet0/1/0.1 Interface
Route Port,The Maximum Transmit Unit is 9600
Internet Address is 10.2.1.1/24
IP Sending Frames' Format is PKTFMT_ETHNT_2, Hardware address is 00e0-fc12-7890
Last physical up time   :  2013-07-29 15:39:23
Last physical down time : 2013-07-29 15:38:41
Current system time: 2013-07-30 09:15:33
Statistics last cleared:never
      Last 600 seconds input rate: 23513 bits/sec, 2 packets/sec
      Last 600 seconds output rate: 64319 bits/sec, 3 packets/sec
      Input peak rate 26099 bits/sec, Record time: 2013-07-29 15:40:58
      Output peak rate 64809 bits/sec, Record time: 2013-07-30 03:59:41
      Input: 183126871 bytes, 182525 packets 
      Output: 509287017 bytes, 244628 packets
    Input:
      Unicast: 55 packets, Multicast: 160762 packets
      Broadcast: 21708 packets, JumboOctets: 31031 packets
      CRC: 0 packets, Symbol: 0 packets
      Overrun: 0 packets, InRangeLength: 0 packets
      LongPacket: 0 packets, Jabber: 0 packets, Alignment: 0 packets
      Fragment: 0 packets, Undersized Frame: 0 packets
      RxPause: 0 packets
    Output:
      Unicast: 53 packets, Multicast: 243990 packets
      Broadcast: 585 packets, JumboOctets: 0 packets
      Lost: 0 packets, Overflow: 0 packets, Underrun: 0 packets
      System: 0 packets, Overruns: 0 packets
      TxPause: 0 packets

Configuration Files

Device A configuration file

#
sysname DeviceA
#
 bfd
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 10.1.1.1 255.255.255.0
#
interface GigabitEthernet0/1/0.1
 undo shutdown
 ip address 10.2.1.1 255.255.255.0
#
bfd pissub bind peer-ip default-ip interface GigabitEthernet0/1/0
 discriminator local 1
 discriminator remote 2
 process-interface-status sub-if
return

Device B configuration file

#
 sysname DeviceB
#
 bfd
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 10.1.1.2 255.255.255.0
#
interface GigabitEthernet0/1/0.1
 undo shutdown
 ip address 10.2.1.2 255.255.255.0
#
bfd pissub bind peer-ip default-ip interface GigabitEthernet0/1/0
 discriminator local 2
 discriminator remote 1
 process-interface-status sub-if
return

Example for Enabling BFD to Modify the PST

This section provides an example for enabling BFD to modify the PST. After the configuration is complete, an upper-layer protocol switches traffic to a backup link if a link fault occurs.

Networking Requirements

If BFD is enabled to modify the PST, BFD can modify the PST after detecting that an interface goes Down. This function allows the lower layer to detect the fault based on the PST change.

LDP FRR and IP FRR obtain a BFD detection result based on a PST change.

On the network shown in Figure 3-19, a BFD session in asynchronous mode is set up to detect faults in the link between Device A and Device B.

Figure 3-19 Enabling BFD to modify the PST

Interfaces 1 in this example are GE 0/1/0.

Precautions

BFD sessions must be established on both ends.

Configuration Roadmap

The configuration roadmap is as follows:

Enable BFD globally on Device A and Device B.
Create single-hop BFD sessions and bind them to the outbound interfaces on Device A and Device B, respectively.
Enable BFD to modify the PST.

Data Preparation

To complete the configuration, you need the following data:

Peer IP address monitored by BFD
Local and remote discriminators of BFD sessions
BFD session names

Procedure

Assign IP addresses to the interfaces connecting Device A and Device B.

# Configure Device A.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceA

[*HUAWEI] commit

[~DeviceA] interface gigabitethernet 0/1/0

[~DeviceA-GigabitEthernet0/1/0] undo shutdown

[*DeviceA-GigabitEthernet0/1/0] ip address 10.1.1.1 24

[*DeviceA-GigabitEthernet0/1/0] commit

[~DeviceA-GigabitEthernet0/1/0] quit

[~DeviceA] quit

# Configure Device B.

<HUAWEI> system-view

[~HUAWEI] sysname DeviceB

[*HUAWEI] commit

[~DeviceB] interface gigabitethernet 0/1/0

[~DeviceB-GigabitEthernet0/1/0] undo shutdown

[*DeviceB-GigabitEthernet0/1/0] ip address 10.1.1.2 24

[*DeviceB-GigabitEthernet0/1/0] commit

[~DeviceB-GigabitEthernet0/1/0] quit

[~DeviceB] quit

After the configuration is complete, Device A and Device B can ping each other. The following example uses the command output on Device A.

<DeviceA> ping 10.1.1.2

PING 10.1.1.2 : 56  data bytes, press CTRL_C to break
    Reply from 10.1.1.2: bytes=56 Sequence=1 ttl=255 time=3 ms
    Reply from 10.1.1.2: bytes=56 Sequence=2 ttl=255 time=1 ms
    Reply from 10.1.1.2: bytes=56 Sequence=3 ttl=255 time=1 ms
    Reply from 10.1.1.2: bytes=56 Sequence=4 ttl=255 time=1 ms
    Reply from 10.1.1.2: bytes=56 Sequence=5 ttl=255 time=1 ms

  --- 10.1.1.2 ping statistics ---
    5 packet(s) transmitted
    5 packet(s) received
    0.00% packet loss
    round-trip min/avg/max = 1/1/3 ms

Configure single-hop BFD.

# Configure Device A.

[~DeviceA] bfd

[*DeviceA-bfd] quit

[*DeviceA] bfd pst bind peer-ip 10.1.1.2 interface gigabitethernet 0/1/0

[*DeviceA-bfd-session-pst] discriminator local 1

[*DeviceA-bfd-session-pst] discriminator remote 2

[*DeviceA-bfd-session-pst] commit

[~DeviceA-bfd-session-pst] quit

# Configure Device B.

[~DeviceB] bfd

[*DeviceB-bfd] quit

[*DeviceB] bfd pst bind peer-ip 10.1.1.1 interface gigabitethernet 0/1/0

[*DeviceB-bfd-session-pst] discriminator local 2

[*DeviceB-bfd-session-pst] discriminator remote 1

[*DeviceB-bfd-session-pst] commit

[~DeviceB-bfd-session-pst] quit

After completing the configurations, run the display bfd session all verbose command on Device A or Device B. The command output shows that a single-hop BFD session has been established and its status is Up. The following example uses the command output on Device B.

[~DeviceB] display bfd session all verbose

(w): State in WTR  (*): State is invalid
------------------------------------------------------------------------------
  (One Hop)   State : Up                    Name : pst
------------------------------------------------------------------------------
  Local Discriminator    : 2                Remote Discriminator   : 1
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(GigabitEthernet0/1/0)
  Bind Session Type      : Static
  Bind Peer IP Address   : 10.1.1.1
  Bind Interface         : GigabitEthernet0/1/0
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255
  Proc Interface Status  : Disable          Process PST            : Disable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : 0                Session Detect TmrID   : 0
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 1/0

Enable BFD to modify the PST on Device A and Device B.

# Configure Device A.

[~DeviceA] bfd pst

[*DeviceA-bfd-session-pst] process-pst

[*DeviceA-bfd-session-pst] commit

[~DeviceA-bfd-session-pst] quit

# Configure Device B.

[~DeviceB] bfd pst

[*DeviceB-bfd-session-pst] process-pst

[*DeviceB-bfd-session-pst] commit

[~DeviceB-bfd-session-pst] quit

Verify the configuration.

After completing the configurations, run the display bfd session all verbose command on Device A or Device B. The command output shows that Process PST is Enable. The following example uses the command output on Device B.

[~DeviceB] display bfd session all verbose

(w): State in WTR  (*): State is invalid
------------------------------------------------------------------------------
  (One Hop)   State : Up                    Name : pst
------------------------------------------------------------------------------
  Local Discriminator    : 2                Remote Discriminator   : 1
  Session Detect Mode    : Asynchronous Mode Without Echo Function
  BFD Bind Type          : Interface(GigabitEthernet0/1/0)
  Bind Session Type      : Static
  Bind Peer IP Address   : 10.1.1.1
  Bind Interface         : GigabitEthernet0/1/0
  FSM Board Id           : 1                TOS-EXP                : 7
  Min Tx Interval (ms)   : 10               Min Rx Interval (ms)   : 10
  Actual Tx Interval (ms): 10               Actual Rx Interval (ms): 10
  Local Detect Multi     : 3                Detect Interval (ms)   : 30
  Echo Passive           : Disable          Acl Number             : -
  Destination Port       : 3784             TTL                    : 255
  Proc Interface Status  : Disable          Process PST         : Enable
  WTR Interval (ms)      : 0                Local Demand Mode      : Disable
  Active Multi           : 3
  Last Local Diagnostic  : No Diagnostic
  Bind Application       : No Application Bind
  Session TX TmrID       : 0                Session Detect TmrID   : 0
  Session Init TmrID     : -                Session WTR TmrID      : -
  Session Echo Tx TmrID  : -
  Session Description    : -
------------------------------------------------------------------------------

     Total UP/DOWN Session Number : 1/0

Configuration Files

Device A configuration file

#
sysname DeviceA
#
bfd
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 10.1.1.1 255.255.255.0
#
bfd pst bind peer-ip 10.1.1.2 interface GigabitEthernet0/1/0
 discriminator local 1
 discriminator remote 2
 process-pst
return

Device B configuration file

#
sysname DeviceB
#
bfd
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 10.1.1.2 255.255.255.0
#
bfd pst bind peer-ip 10.1.1.1 interface GigabitEthernet0/1/0
 discriminator local 2
 discriminator remote 1
 process-pst
return

Example for Configuring Static BFD for TE with Automatically Negotiated Discriminators

Static BFD for TE is configured to rapidly detect tunnel faults and perform a traffic switchover.

Networking Requirements

On the MPLS network shown in Figure 3-20, MPLS TE tunnels are established between PE1 and PE2. The tunnels are detected using static BFD sessions with automatically negotiated discriminators.

Figure 3-20 Networking diagram for configuring static BFD for TE with automatically negotiated discriminators

Interface 1 in this example represents GE 0/1/1.

Configuration Notes

None

Configuration Roadmap

The configuration roadmap is as follows:

Configure an MPLS network and establish bidirectional TE tunnels between PE1 and PE2.
Enable BFD globally on PE1 and PE2.
Configure static BFD with automatically negotiated discriminators on PE1 and PE2 to monitor TE tunnels.

Data Preparation

To complete the configuration, you need the following data:

MPLS LSR IDs
Interface number of and bandwidth consumed by each tunnel, and name of an explicit path over which each tunnel is established
Name of a BFD session

Procedure

Assign an IP address to each interface.
Assign an IP address to each interface according to Figure 3-20, create loopback interfaces on routers, and configure the IP addresses of the loopback interfaces as MPLS LSR IDs. For configuration details, see Configuration Files in this section.
Configure an IGP.
Configure OSPF or IS-IS on each router to ensure interworking between PE1 and PE2. OSPF is used in the example. For configuration details, see Configuration Files in this section.
Configure basic MPLS TE functions.
On each router, configure an LSR ID and enable MPLS in the system and interface views. For configuration details, see Configuration Files in this section.
Configure basic MPLS TE functions.
On each router, enable MPLS-TE in the MPLS and interface views. For configuration details, see Configuration Files in this section.
Enable OSPF TE and configure CSPF.
Enable OSPF TE on each router and configure CSPF on PE1. For configuration details, see Configuration Files in this section.

Configure a tunnel interface on each PE.

# Configure PE1.

[*PE1] interface tunnel 1

[*PE1-Tunnel1] ip address unnumbered interface loopback 0

[*PE1-Tunnel1] tunnel-protocol mpls te

[*PE1-Tunnel1] destination 2.2.2.2

[*PE1-Tunnel1] mpls te tunnel-id 1

[*PE1-Tunnel1] commit

[~PE1-Tunnel1] quit

# Configure PE2.

[~PE2] interface tunnel 2

[*PE2-Tunnel2] ip address unnumbered interface loopback 0

[*PE2-Tunnel2] tunnel-protocol mpls te

[*PE2-Tunnel2] destination 1.1.1.1

[*PE2-Tunnel2] mpls te tunnel-id 2

[*PE2-Tunnel2] commit

[~PE2-Tunnel2] quit

Configure static BFD with automatically negotiated discriminators to detect TE tunnel faults.

# Configure PE1.

[*PE1] bfd aaa bind mpls-te interface Tunnel0/0/1 reverse-te lsr-id 2.2.2.2 tunnel-id 1 auto

# Configure PE2.

[*PE2] bfd bbb bind mpls-te interface Tunnel0/0/2 reverse-te lsr-id 1.1.1.1 tunnel-id 1 auto

Verify the configuration.

After completing the preceding configuration, run the display bfd session all command on PE2 to view information about the configured BFD session.

[*PE2]display bfd session all 
(w): State in WTR
(*): State is invalid
--------------------------------------------------------------------------------
Local      Remote     PeerIpAddr      State     Type        InterfaceName 
--------------------------------------------------------------------------------
16385      16385       1.1.1.1         UP      AUTO_TE_TNL    Tunnel0/0/2
--------------------------------------------------------------------------------

Configuration Files

PE1 configuration file

 sysname PE1

bfd

 mpls lsr-id 1.1.1.1

 mpls

  mpls te

  mpls rsvp-te

  mpls te cspf

interface gigabitethernet0/1/1

 undo shutdown

 ip address 10.1.1.1 255.255.255.0

 mpls

 mpls te

 mpls rsvp-te

interface LoopBack0

 ip address 1.1.1.1 255.255.255.255

interface Tunnel0/0/1

 ip address unnumbered interface LoopBack1

 tunnel-protocol mpls te

 destination 2.2.2.2

 mpls te tunnel-id 1

ospf 1
 opaque-capability enable
 area 0.0.0.0
  network 1.1.1.1 0.0.0.0
  network 10.1.1.0 0.0.0.255
  mpls-te enable
#
bfd aaa bind mpls-te interface Tunnel0/0/1 reverse-te lsr-id 2.2.2.2 tunnel-id 2 auto
#
return

PE2 configuration file

 sysname PE2

bfd

 mpls lsr-id 3.3.3.3

 mpls

  mpls te

  mpls rsvp-te

  mpls te cspf

interface gigabitethernet0/1/1

 undo shutdown

 ip address 10.2.1.2 255.255.255.0

 mpls

 mpls te

 mpls rsvp-te

interface LoopBack0

 ip address 3.3.3.3 255.255.255.255

interface Tunnel0/0/2

 ip address unnumbered interface LoopBack1

 tunnel-protocol mpls te

 destination 1.1.1.1

 mpls te tunnel-id 2

ospf 1
 opaque-capability enable
 area 0.0.0.0
  network 2.2.2.2 0.0.0.0
  network 10.1.1.0 0.0.0.255
  mpls-te enable
#
bfd bbb bind mpls-te interface Tunnel0/0/2 reverse-te lsr-id 1.1.1.1 tunnel-id 1 auto

return

Example for Configuring Single-Hop BFD for a Layer 3 Eth-Trunk
Example for Configuring BFD to Monitor VPN Routes
Example for Configuring BFD for Static VPN Routes
Example for Configuring Multi-hop BFD
Example for Configuring Single-hop BFD for IPv6
Example for Configuring Multi-hop BFD for IPv6
Example for Configuring Sub-Interfaces for QinQ VLAN Tag Termination to Support BFD
Example for Configuring Sub-Interfaces for Dot1q VLAN Tag Termination to Support BFD
Example for Configuring a BFD for Link-Bundle Session to Detect Layer 3 Eth-Trunk Member Link Faults
Example for Configuring a BFD for Link-Bundle Session to Detect Layer 3 Eth-Trunk Member Link Faults (IPv6)
Example for Configuring a One-Arm BFD Echo Session
Example for Configuring the Delay of a BFD Session to Go Up
Example for Associating a BFD Session with an Interface
Example for Associating a BFD Session and a Sub-interface
Example for Enabling BFD to Modify the PST
Example for Configuring Static BFD for TE with Automatically Negotiated Discriminators

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Updated: 2020-07-02

Document ID: EDOC1100146989

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Example for Configuring Single-Hop BFD for a Layer 3 Eth-Trunk

Networking Requirements

Precautions

Configuration Roadmap

Data Preparation

Procedure

Configuration Files

Example for Configuring BFD to Monitor VPN Routes

Networking Requirements

Configuration Roadmap

Data Preparation

Procedure

Configuration Files

Example for Configuring BFD for Static VPN Routes

Networking Requirements

Configuration Notes

Configuration Roadmap

Data Preparation

Procedure

Configuration Files

Example for Configuring Multi-hop BFD

Networking Requirements

Precautions

Configuration Roadmap

Data Preparation

Procedure

Configuration Files

Example for Configuring Single-hop BFD for IPv6

Networking Requirements

Precautions

Configuration Roadmap

Data Preparation

Procedure

Configuration Files

Example for Configuring Multi-hop BFD for IPv6

Networking Requirements

Precautions

Configuration Roadmap

Data Preparation

Procedure

Configuration Files

Example for Configuring Sub-Interfaces for QinQ VLAN Tag Termination to Support BFD

Networking Requirements

Configuration Roadmap

Data Preparation

Procedure

Configuration Files

Example for Configuring Sub-Interfaces for Dot1q VLAN Tag Termination to Support BFD

Networking Requirements

Configuration Roadmap

Data Preparation

Procedure

Configuration Files

Example for Configuring a BFD for Link-Bundle Session to Detect Layer 3 Eth-Trunk Member Link Faults

Networking Requirements

Configuration Roadmap

Data Preparation

Procedure

Configuration Files

Example for Configuring a BFD for Link-Bundle Session to Detect Layer 3 Eth-Trunk Member Link Faults (IPv6)

Networking Requirements

Configuration Roadmap

Data Preparation

Procedure

Configuration Files

Example for Configuring a One-Arm BFD Echo Session

Networking Requirements

Configuration Roadmap