3Com 10014299 manual Normally, Troubleshooting an, Ospf Configuration

446CHAPTER 29: CONFIGURING OSPF

[RouterB] ospf enable

[RouterB] interface ethernet 0 [RouterB-Ethernet0] ip address 192.1.1.2 255.255.255.0

[RouterB-Ethernet0] ospf enable area 0

[RouterB-Ethernet0]ospf authentication-mode simple 3Com

3Configure Router C:

	[RouterC] router id 3.3.3.3
	[RouterC] ospf enable
	[RouterC-ospf]interface serial 0
	[RouterC-Serial0]ip address 193.1.1.2 255.255.255.0
	[RouterC-Serial0] ospf enable area 1
	[RouterC-Serial0]ospf authentication-mode md5 3Com 11
Troubleshooting an	You have configured OSPF as described previously, but router OSPF fails to run
OSPF Configuration	normally.

Perform the following procedures:

1Troubleshoot the local area: First check whether the protocol between the two directly connected routers is running normally. If the peer state machine between the two routers is in FULL status, it means the protocol is running normally. (Note that on broadcast network and NBMA network, the peer state machine between two DROther routers is not in FULL status but in 2 way status. DR, BDR and all other routers are in FULL status).

Use the display ospf peer command to view:

[Router] display ospf peer

Interface: 202.38.160.1		Area: 0.0.0.2
Neighbors:
RouterID: 2.2.2.2		Address: 202.38.160.2
State:FULL Mode:	None	Priority: 0
DR: 202.38.160.1	BDR: 202.38.160.1
Last Hello: 14:04	Last Exchange: 0

Authentication Sequence: a51dac

View OSPF information on the interface with the display ospf interface command.

■Check whether the physical connection and low layer protocol are running normally. If the opposite router cannot ping through the local router, it means that the physical connection and lower layer protocol are faulty.

■If the physical connection and lower layer protocol are normal, check the OSPF parameters configured on the interface. The parameters must be the same as those of the adjacent routers of this interface. The parameters include hellointerval, deadinterval and authentication. The area-id must be the same and the network segment and mask must be consistent (the network segment and mask of point-to-point and virtual link can be different).

■Check whether the deadinterval value is at least 4 times the hellointerval value on the same interface.

■If the network type is NBMA or point-to-multipoint, or the interface type is manually modified to point-to-point, use command ospf network-type p2p to manually specify the peer. In addition, when two routers are connected in