Example for Associating Interface Backup with NQA to Configure an ADSL Interface as the Backup of an Ethernet Interface
Networking Requirements
As shown in Figure 2-23, the egress gateway RouterA in the headquarters of company connects to the Internet through GE1/0/0. The link between GE1/0/0 and the Internet is used as the primary link, and the link between ATM0/0/0 (ADSL interface) and the Internet is used as the backup link.
The company wants to monitor the primary link status. When the primary link is faulty, the backup link is started to transmit services to reduce the impact of the primary link fault on service transmission.
Configuration Roadmap
The configuration roadmap is as follows:
Configure IP addresses for interfaces on routes along the primary link and static routes to ensure connectivity at the network layer.
Configure RS-DCC on RouterA so that the backup link transmits services.
Configure an NQA test instance on RouterA to monitor the primary link status in real time.
Associate interface backup with NQA on backup interface ATM0/0/0 of RouterA. When the NQA test instance detects a fault on the primary link, traffic can be rapidly switched to the backup interface.
Procedure
- Implement connectivity at the network layer.
# Assign an IP address to the interface of RouterA.
<Huawei> system-view [Huawei] sysname RouterA [RouterA] interface gigabitethernet1/0/0 [RouterA-GigabitEthernet1/0/0] ip address 2.1.1.1 255.255.255.0 [RouterA-GigabitEthernet1/0/0] quit
# Assign an IP address to the interface of RouterB.
<Huawei> system-view [Huawei] sysname RouterB [RouterB] interface gigabitethernet1/0/0 RouterB-GigabitEthernet1/0/0] ip address 4.1.1.2 255.255.255.0 [RouterB-GigabitEthernet1/0/0] quit
# Assign an IP address to the interface of RouterC.
<Huawei> system-view [Huawei] sysname RouterC [RouterC] interface gigabitethernet1/0/0 [RouterC-GigabitEthernet1/0/0] ip address 2.1.1.2 255.255.255.0 [RouterC-GigabitEthernet1/0/0] quit
# Assign an IP address to the interface of RouterD.
[RouterD] interface gigabitethernet1/0/0 [RouterD-GigabitEthernet1/0/0] ip address 4.1.1.1 255.255.255.0 [RouterD-GigabitEthernet1/0/0] quit
# On RouterA, configure a static route to 4.1.1.0/24 of RouterB.
[RouterA] ip route-static 4.1.1.0 255.255.255.0 2.1.1.2 preference 80# On RouterB, configure a static route to 2.1.1.0/24 of RouterA.
[RouterB] ip route-static 2.1.1.0 255.255.255.0 4.1.1.1 preference 80 - Configure RS-DCC on RouterA.
# Configure a dialer interface.
[RouterA] dialer-rule [RouterA-dialer-rule] dialer-rule 10 ip permit [RouterA-dialer-rule] quit [RouterA] interface dialer 1 [RouterA-Dialer1] dialer user u1 [RouterA-Dialer1] dialer-group 10 [RouterA-Dialer1] dialer bundle 10 [RouterA-Dialer1] ip address 3.1.1.1 255.255.255.0 [RouterA-Dialer1] dialer number 666 [RouterA-Dialer1] quit
# Configure the ATM interface.
[RouterA] interface atm 0/0/0 [RouterA-Atm0/0/0] pvc pppoa 2/40 [RouterA-atm-pvc-Atm0/0/0-2/40-pppoa] map ppp dialer 1 [RouterA-atm-pvc-Atm0/0/0-2/40-pppoa] quit [RouterA-Atm0/0/0] quit
# Configure a static route for the backup link.[RouterA] ip route-static 5.1.1.0 255.255.255.0 dialer1 preference 60 - Configure the DSLAM.
See the DSLAM documentation.
- Configure the PPPoA server.
Assign IP address 3.1.1.2 to the PPPoA server.
- Configure an NQA test instance with the destination address of 4.1.1.2/24.
# Configure the ICMP NQA test instance on RouterA.
[RouterA] nqa test-instance user test [RouterA-nqa-user-test] test-type icmp [RouterA-nqa-user-test] destination-address ipv4 4.1.1.2 [RouterA-nqa-user-test] frequency 10 [RouterA-nqa-user-test] start now
- Configure association between interface backup and NQA on backup interface ATM0/0/0.
[RouterA]interface atm 0/0/0 [RouterA-Atm0/0/0] standby track nqa user test
- Verify the configuration.
Run the display nqa results test-instance user test command. The command output shows that the NQA test instance status is success.
[RouterA] display nqa results test-instance user test NQA entry(user, test) :testflag is active ,testtype is icmp 1 .Test 1 result The test is finished Send operation times: 3 Receive response times: 3 Completion:success RTD OverThresholds number: 0 Attempts number:1 Drop operation number:0 Disconnect operation number:0 Operation timeout number:0 System busy operation number:0 Connection fail number:0 Operation sequence errors number:0 RTT Stats errors number:0 Destination ip address:4.1.1.2 Min/Max/Average Completion Time: 60/90/80 Sum/Square-Sum Completion Time: 240/19800 Last Good Probe Time: 2011-04-19 16:38:38.7 Lost packet ratio: 0 %# Run the display standby interface command on RouterA to view the NQA test instance status and backup interface status. The command output shows that the NQA test instance status is OK and the status of ATM0/0/0 is STANDBY.
<RouterA> display standby state Interface Interfacestate Backupstate Backupflag Pri Loadstate Backup-flag meaning: M---MAIN B---BACKUP V---MOVED U---USED D---LOAD P---PULLED ---------------------------------------------------------------------------- Below is track BFD information: Bfd-Name Bfd-State BackupInterface State ---------------------------------------------------------------------------- Below is track IP route information: Destination/Mask Route-State BackupInterface State -------------------------------------------------------------------------------- Below is track NQA Information: Instance Name BackupInterface State user test OK Atm0/0/0 STANDBYRun the shutdown command on GE1/0/0 of RouterA to simulate a link fault. Run the display nqa results test-instance user test command on RouterA. The command output shows that the NQA test instance status is failed.
[RouterA] display nqa results test-instance user test NQA entry(user, test) :testflag is active ,testtype is icmp 1 .Test 1 result The test is finished Send operation times: 3 Receive response times: 0 Completion:failed RTD OverThresholds number: 0 Attempts number:1 Drop operation number:3 Disconnect operation number:0 Operation timeout number:0 System busy operation number:0 Connection fail number:0 Operation sequence errors number:0 RTT Stats errors number:0 Destination ip address:4.1.1.2 Min/Max/Average Completion Time: 0/0/0 Sum/Square-Sum Completion Time: 0/0 Last Good Probe Time: 0000-00-00 00:00:00.0 Lost packet ratio: 100 %After 10s, run the display standby state command on RouterA. The command output shows that the NQA test instance status is ERR, and the status of backup interface ATM0/0/0 is Up, indicating that the backup interface has started.
<RouterA> display standby state Interface Interfacestate Backupstate Backupflag Pri Loadstate Backup-flag meaning: M---MAIN B---BACKUP V---MOVED U---USED D---LOAD P---PULLED ---------------------------------------------------------------------------- Below is track BFD information: Bfd-Name Bfd-State BackupInterface State ---------------------------------------------------------------------------- Below is track IP route information: Destination/Mask Route-State BackupInterface State -------------------------------------------------------------------------------- Below is track NQA Information: Instance Name BackupInterface State user test ERR Atm0/0/0 UPRun the undo shutdown command on GE1/0/0 of RouterA to make GE1/0/0 Up. After 10s, run the display standby state command on RouterA. The command output shows that the route status is OK and backup interface ATM0/0/0 has switched to the standby state.
<RouterA> display standby state Interface Interfacestate Backupstate Backupflag Pri Loadstate Backup-flag meaning: M---MAIN B---BACKUP V---MOVED U---USED D---LOAD P---PULLED ---------------------------------------------------------------------------- Below is track BFD information: Bfd-Name Bfd-State BackupInterface State ---------------------------------------------------------------------------- Below is track IP route information: Destination/Mask Route-State BackupInterface State -------------------------------------------------------------------------------- Below is track NQA Information: Instance Name BackupInterface State user test OK Atm0/0/0 STANDBY
Configuration Files
RouterA configuration file
# sysname RouterA # interface Dialer1 link-protocol ppp ip address 3.1.1.1 255.255.255.0 dialer user u1 dialer bundle 10 dialer number 666 dialer-group 10 # interface GigabitEthernet1/0/0 ip address 2.1.1.1 255.255.255.0 # interface Atm0/0/0 pvc pppoa 2/40 map ppp Dialer1 standby track nqa user test # dialer-rule dialer-rule 10 ip permit # ip route-static 4.1.1.0 255.255.255.0 2.1.1.2 preference 80 ip route-static 5.1.1.0 255.255.255.0 Dialer1 # nqa test-instance user test test-type icmp destination-address ipv4 4.1.1.2 frequency 10 # return
RouterB configuration file
# sysname RouterB # interface GigabitEthernet1/0/0 ip address 4.1.1.2 255.255.255.0 # ip route-static 2.1.1.0 255.255.255.0 4.1.1.1 preference 80 ip route-static 3.1.1.0 255.255.255.0 Dialer1 # return
Configuration file of RouterC
# sysname RouterC # interface GigabitEthernet1/0/0 ip address 2.1.1.2 255.255.255.0 # returnRouterD configuration file
# sysname RouterD # interface GigabitEthernet1/0/0 ip address 4.1.1.1 255.255.255.0 # return
