Example for Configuring OSPF Virtual Links
Networking Requirements
As shown in Figure 5-36, Area 2 does not connect to the backbone area directly. Area 1 serves as a transit area to connect Area 2 and Area 0. A virtual link is configured between Router A and Router B.
Configuration Roadmap
The configuration roadmap is as follows:
Configure basic OSPF functions on each router.
Configure virtual connections on Router A and Router B to connect the backbone area with the non-backbone area.
Procedure
- Configure an IP address for each interface.
# Configure Router A.
<Huawei> system-view
[Huawei] sysname RouterA[RouterA] interface gigabitethernet 1/0/0[RouterA-GigabitEthernet1/0/0] ip address 192.168.1.1 24[RouterA-GigabitEthernet1/0/0] quit[RouterA] interface gigabitethernet 2/0/0[RouterA-GigabitEthernet2/0/0] ip address 10.1.1.1 8[RouterA-GigabitEthernet2/0/0] quitThe configurations of Router B, Router C, Router D, Router E, and Router F are similar to the configuration of Router A, and are not mentioned here.
- Configure basic OSPF functions.
# Configure Router A.
[RouterA] ospf 1 router-id 1.1.1.1[RouterA-ospf-1] area 0[RouterA-ospf-1-area-0.0.0.0] network 10.0.0.0 0.255.255.255[RouterA-ospf-1-area-0.0.0.0] quit[RouterA-ospf-1] area 1[RouterA-ospf-1-area-0.0.0.1] network 192.168.1.0 0.0.0.255[RouterA-ospf-1-area-0.0.0.1] quit# Configure Router B.
[RouterB] ospf 1 router-id 2.2.2.2[RouterB-ospf-1] area 1[RouterB-ospf-1-area-0.0.0.1] network 192.168.1.0 0.0.0.255[RouterB-ospf-1-area-0.0.0.1] quit[RouterB-ospf-1] area 2[RouterB-ospf-1-area-0.0.0.2] network 172.16.0.0 0.0.255.255[RouterB-ospf-1-area-0.0.0.2] quit# Configure Router C.
[RouterC] ospf 1 router-id 3.3.3.3[RouterC-ospf-1] area 0[RouterC-ospf-1-area-0.0.0.0] network 10.0.0.0 0.255.255.255[RouterC-ospf-1-area-0.0.0.0] quit# Configure Router D.
[RouterD] ospf 1 router-id 4.4.4.4[RouterD-ospf-1] area 2[RouterD-ospf-1-area-0.0.0.2] network 172.16.0.0 0.0.255.255[RouterD-ospf-1-area-0.0.0.2] quit# View the OSPF routing table of Router A.
The routing table of Router A does not contain routes in Area 2 because Area 2 is not directly connected to Area 0.
[RouterA] display ospf routingOSPF Process 1 with Router ID 1.1.1.1
Routing Tables
Routing for Network
Destination Cost Type NextHop AdvRouter Area
10.0.0.0/8 1 Transit 10.1.1.1 1.1.1.1 0.0.0.0
192.168.1.0/24 1 Transit 192.168.1.1 1.1.1.1 0.0.0.1
Total Nets: 2
Intra Area: 2 Inter Area: 0 ASE: 0 NSSA: 0
- Configure virtual links.
# Configure Router A.
[RouterA] ospf 1[RouterA-ospf-1] area 1[RouterA-ospf-1-area-0.0.0.1] vlink-peer 2.2.2.2[RouterA-ospf-1-area-0.0.0.1] quit[RouterA-ospf-1] quit# Configure Router B.
[RouterB] ospf 1[RouterB-ospf-1] area 1[RouterB-ospf-1-area-0.0.0.1] vlink-peer 1.1.1.1[RouterB-ospf-1-area-0.0.0.1] quit[RouterB-ospf-1] quit - Verify the configuration.
# View the OSPF routing table of Router A.
[RouterA] display ospf routingOSPF Process 1 with Router ID 1.1.1.1
Routing Tables
Routing for Network
Destination Cost Type NextHop AdvRouter Area
172.16.0.0/16 2 Inter-area 192.168.1.2 2.2.2.2 0.0.0.2
10.0.0.0/8 1 Transit 10.1.1.1 1.1.1.1 0.0.0.0
192.168.1.0/24 1 Transit 192.168.1.1 1.1.1.1 0.0.0.1
Total Nets: 3
Intra Area: 2 Inter Area: 1 ASE: 0 NSSA: 0
Configuration Files
Configuration file of Router A
#
sysname RouterA#
interface GigabitEthernet1/0/0ip address 192.168.1.1 255.255.255.0
#
interface GigabitEthernet2/0/0ip address 10.1.1.1 255.0.0.0
#
ospf 1 router-id 1.1.1.1
area 0.0.0.0
network 10.0.0.0 0.255.255.255
area 0.0.0.1
network 192.168.1.0 0.0.0.255
vlink-peer 2.2.2.2
#
return
Configuration file of Router B
#
sysname RouterB#
interface GigabitEthernet1/0/0ip address 192.168.1.2 255.255.255.0
#
interface GigabitEthernet2/0/0ip address 172.16.1.1 255.255.0.0
#
ospf 1 router-id 2.2.2.2
area 0.0.0.1
network 192.168.1.0 0.0.0.255
vlink-peer 1.1.1.1
area 0.0.0.2
network 172.16.0.0 0.0.255.255
#
return
Configuration file of Router C
#
sysname RouterC#
interface GigabitEthernet2/0/0ip address 10.1.1.2 255.0.0.0
#
ospf 1 router-id 3.3.3.3
area 0.0.0.0
network 10.0.0.0 0.255.255.255
#
return
Configuration file of Router D
#
sysname RouterD#
interface GigabitEthernet2/0/0ip address 172.16.1.2 255.255.0.0
#
ospf 1 router-id 4.4.4.4
area 0.0.0.2
network 172.16.0.0 0.0.255.255
#
return
