111
Authentication Sequence: [ 0 ]
Router ID: 2.2.2.2 Address: 192.168.1.2 GR State: Normal
State: 2-Way Mode: None Priority: 0
DR: 192.168.1.1 BDR: 192.168.1.3 MTU: 0
Options is 0x02 (-|-|-|-|-|-|E|-)
Dead timer due in 35 sec
Neighbor is up for 00:01:44
Authentication Sequence: [ 0 ]
Router ID: 3.3.3.3 Address: 192.168.1.3 GR State: Normal
State: Full Mode: Nbr is Slave Priority: 2
DR: 192.168.1.1 BDR: 192.168.1.3 MTU: 0
Options is 0x02 (-|-|-|-|-|-|E|-)
Dead timer due in 39 sec
Neighbor is up for 00:01:41
Authentication Sequence: [ 0 ]
The output shows that Router A becomes the DR and Router C becomes the BDR.
The
full
neighbor state means an adjacency has been established. The
2-way
neighbor state
means the two routers are not the DR or BDR, and they do not exchange LSAs.
# Display OSPF interface information.
[RouterA] display ospf interface
OSPF Process 1 with Router ID 1.1.1.1
Interfaces
Area: 0.0.0.0
IP Address Type State Cost Pri DR BDR
192.168.1.1 Broadcast DR 1 100 192.168.1.1 192.168.1.3
[RouterB] display ospf interface
OSPF Process 1 with Router ID 2.2.2.2
Interfaces
Area: 0.0.0.0
IP Address Type State Cost Pri DR BDR
192.168.1.2 Broadcast DROther 1 0 192.168.1.1 192.168.1.3
The interface state
DROther
means the interface is not the DR or BDR.
OSPF virtual link configuration example
Network requirements
Configure a virtual link between Router B and Router C to connect Area 2 to the backbone area. After
configuration, Router B can learn routes to Area 2.