Operation Manual – IPv4 RoutingH3C S7500E Series Ethernet Switches Chapter 3 OSPF Configuration3-593.10 Troubleshooting OSPF Configuration3.10.1 No OSPF Neighbor Relationship EstablishedI. SymptomNo OSPF neighbor relationship can be established.II. AnalysisIf the physical link and lower layer protocols work well, check OSPF parametersconfigured on interfaces. Two neighbors must have the same parameters, such as thearea ID, network segment and mask (a P2P or virtual link may have different networksegments and masks), network type. If the network type is broadcast or NBMA, at leastone interface must have a router priority higher than 0.III. Processing steps1) 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 timesthe hello interval.5) On an NBMA network, using the peer ip-address command to specify theneighbor manually is required.6) On an NBMA or a broadcast network, at least one connected interface must havea router priority higher than 0.3.10.2 Incorrect Routing InformationI. SymptomOSPF cannot find routes to other areas.II. AnalysisThe backbone area must maintain connectivity to all other areas. If a router connects tomore than one area, at least one area must be connected to the backbone. Thebackbone cannot be configured as a Stub area.In a Stub area, all routers cannot receive external routes, and all interfaces connectedto the Stub area must belong to the Stub area.III. Solution1) 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 Link State Database to checkits integrity.
