Configuring Virtual Links - Allied Telesis SwitchBlade x908 Series Software Reference Manual

OSPF Configuration

Configuring Virtual Links

Virtual links are used to connect a disjointed non-backbone area to the backbone area, or to
repair a non-contiguous backbone area. In this example, the OSPF routers shown represent
any Allied Telesis managed Layer 3 switches or Allied Telesis routers.
In the network below, there is no area border router that connects Area2 to the backbone. So
a virtual link needs to be created between ABR Device 1 and ABR Device 2 to connect Area
2 to Area 0. Area 1 is used as a transit area.
Device 1
awplus#configure terminal
awplus(config)#router ospf 100
awplus(config-router)#ospf router-id
10.10.21.1
awplus(config-router)#network 10.10.21.0/
24 area 0
awplus(config-router)#network 10.10.22.0/
24 area 1
awplus(config-router)#area 1 virtual-link
10.10.23.2
35.10
Device 6
10.10.21.0/24
Area 0
Software Reference for SwitchBlade® x908, x900 and x600 Series Switches
TM
AlliedWare Plus Operating System - Software Version 5.3.1
Device 1
Area Border
Router
10.10.22.0/24
Virtual
Link
Area 1
Area 2
Device 5
10.10.24.0/24
Enter the Configure mode.
Configure the Routing process and specify the Process ID
(100). The Process ID should be a unique positive
integer identifying the routing process.
Configure OSPF Router ID (10.10.21.1) for this
router.
Define interfaces on which OSPF runs and associate the
area IDs (0 and 1) with the interface.
Configure a virtual link between this router R1 and R2
(Router ID 10.10.23.2) through transit area 1.
Device 4
10.10.22.0/24
10.10.23.0/24
10.10.23.0/24
Device 2
Area Border
Router
10.10.24.0/24
ospf_6
C613-50007-01 REV B