• Have you enabled OSPF globally?• Is the OSPF process active on the interface?• Are adjacencies established correctly?• Are the interfaces configured for Layer 3 correctly?• Is the router in the correct area type?• Have the routes been included in the OSPF database?• Have the OSPF routes been included in the routing table (not just the OSPF database)?Some useful troubleshooting commands are:• show interfaces• show protocols• debug IP OSPF events and/or packets• show neighbors• show routesTo help troubleshoot OSPFv2, use the following commands.• View the summary of all OSPF process IDs enables on the router.EXEC Privilege modeshow running-config ospf• View the summary information of the IP routes.EXEC Privilege modeshow ip route summary• View the summary information for the OSPF database.EXEC Privilege modeshow ip ospf database• View the configuration of OSPF neighbors connected to the local router.EXEC Privilege modeshow ip ospf neighbor• View the LSAs currently in the queue.EXEC Privilege modeshow ip ospf timers rate-limit• View debug messages.EXEC Privilege modedebug ip ospf process-id [event | packet | spf | database-timers rate-limit]To view debug messages for a specific OSPF process ID, use the debug ip ospf process-id command.If you do not enter a process ID, the command applies to the first OSPF process.To view debug messages for a specific operation, enter one of the optional keywords:• event: view OSPF event messages.• packet: view OSPF packet information.• spf: view SPF information.• database-timers rate-limit: view the LSAs currently in the queue.Open Shortest Path First (OSPFv2 and OSPFv3) 619
