Troubleshooting ospf configuration, No ospf neighbor relationship established, Symptom – H3C Technologies H3C S10500 Series Switches User Manual
Page 148: Analysis, Solution, Incorrect routing information
133
Troubleshooting OSPF configuration
No OSPF neighbor relationship established
Symptom
No OSPF neighbor relationship can be established.
Analysis
If the physical link and lower layer protocols work well, check OSPF parameters configured on interfaces.
Two neighbors must have the same parameters, such as the area ID, network segment, and mask (a P2P
or virtual link may have different network segments and masks).
Solution
1.
Display OSPF neighbor information using the display ospf peer command.
2.
Display OSPF interface information using the display ospf interface command.
3.
Ping the neighbor router’s IP address to check connectivity.
4.
Check OSPF timers. The dead interval on an interface must be at least four times the hello interval.
5.
On an NBMA network, using the peer ip-address command to specify the neighbor manually is
required.
6.
On an NBMA or a broadcast network, at least one connected interface must have a router priority
higher than 0.
Incorrect routing information
Symptom
OSPF cannot find routes to other areas.
Analysis
The backbone area must maintain connectivity to all other areas. If a router connects to more than one
area, at least one area must be connected to the backbone. The backbone cannot be configured as a
Stub area.
In a Stub area, all routers cannot receive external routes, and all interfaces connected to the Stub area
must belong to the Stub area.
Solution
1.
Use the display ospf peer command to display neighbors.
2.
Use the display ospf interface command to display OSPF interface information.
3.
Use the display ospf lsdb command to display the LSDB to check its integrity.
4.
Display information about area configuration using the display current-configuration
configuration ospf command. If more than two areas are configured, at least one area is
connected to the backbone.
5.
In a Stub area, all routers attached are configured with the stub command. In an NSSA area, all
routers attached are configured with the nssa command.
6.
If a virtual link is configured, use the display ospf vlink command to check the state of the virtual
link.