The broadcast and point-to-point Open Shortest Path First (OSPF) network types have a default hello timer of 10 seconds and dead timer of 40 seconds. The nonbroadcast, point-to-multipoint, and point-to-multipoint nonbroadcast OSPF network types have a default hello timer of 30 seconds and a dead timer of 120 seconds.
The hello timer is used to specify the amount of time between sending hello packets, and the dead timer is used to specify the amount of time to wait for hello packets before declaring a neighbor to be down. In order for OSPF routers to establish an adjacency, the hello timer on one router should match the hello timer on the other router, and the dead timer on one router should match the dead timer on the other router. The dead timer is set to four times the hello timer value by default.
To manually configure the hello timer interval, you should issue the ip ospf hello interval seconds command in interface configuration mode. To manually configure the dead timer interval, you should issue the ip ospf dead-interval seconds command in interface configuration mode.