Troubleshooting ospf configuration, Symptom, Analysis – H3C Technologies H3C S3600 Series Switches User Manual
Page 356: Solution, Unable to learn a complete network topology
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Troubleshooting OSPF Configuration
Unable to Establish a Neighbor Relationship between Routers
Symptom
No neighbor relationship can be established between neighboring routers.
Analysis
1) Verify that the routers work normally at the link layer.
2) Verify that the conditions for establishing a neighbor relationship are satisfied.
z
OSPF parameters on the interconnected interfaces must be consistent.
z
Area IDs on the interconnected interfaces must be the same.
z
Network ID and subnet masks of the interconnected interfaces must be consistent. (P2P networks
and virtual link are excluded.)
z
The interconnected interfaces have the same type of network.
z
If the network type of the interface on the local router is NBMA, a neighbor must be specified by
using the peer command.
Solution
Perform the following procedure.
1) Use
the
display ip interface brief command to verify that the link layer works normally.
2) Use
the
ping command to check network layer connectivity.
3) Use
the
display ospf interface command to view the OSPF interface configuration.
4) If the network type of an interface is NBMA, use the display current-configuration configuration
ospf command to verify that a neighbor is specified for the router.
5) Use
the
display ospf brief command to check that the OSPF timers are consistent with those on
the neighbor and that the dead time of the neighbor is four times the Hello interval.
6) Use
the
display ospf peer command to view neighbors.
Unable to Learn a Complete Network Topology
Symptom
The router running OSPF is unable to learn a complete network topology.
Analysis
Perform the following procedure to make analyses:
1) If multiple areas are configured on the router, check that one is specified as the backbone area.
2) Check that the backbone area is fully meshed.
3) Check that the backbone area is not configured as a Stub area or NSSA area.
4) Check that no virtual links are configured for the backbone area.
5) For a Stub area, check that the Stub attributes are configured for all routers in the area.
6) For an NSSA area, check that the NSSA attributes are configured for all routers in the area.
7) Check that Stub or NSSA areas are not a transit area of any virtual link. Virtual links cannot pass
through a Stub or NSSA area.
Solution
Perform the following procedure: