234 aid:0.0.0.0 chk:8075 aut:0 auk: from Serial0/1/0 *Mar 23 01:20:55.507: OSPF: rcv. v:2 t:1 l:48 rid:172.16.10.2 aid:0.0.0.0 chk:8076 aut:0 auk: from Serial0/0/0
In the above output, you can see that the router is both sending and receiving Hello packets every 10 seconds from neighbor (adjacent) routers. The next command will provide the same information, but with more detail. For example, you can see the multicast address used (224.0.0.5) and the area:
Router#debug ip ospf hello *Mar 23 01:18:41.103: OSPF: Send hello to 224.0.0.5 area 0 on Serial0/1/0 from 10.1.4.1 *Mar 23 01:18:41.607: OSPF: Send hello to 224.0.0.5 area 0 on FastEthernet0/1 from 10.1.1.1 *Mar 23 01:18:41.607: OSPF: Send hello to 224.0.0.5 area 0 on Serial0/0/0 from 10.1.2.1 *Mar 23 01:18:41.611: OSPF: Send hello to 224.0.0.5 area 0 on Serial0/2/0 from 10.1.5.1 *Mar 23 01:18:41.611: OSPF: Send hello to 224.0.0.5 area 0 on Serial0/0/1 from 10.1.3.1 *Mar 23 01:18:42.199: OSPF: Rcv hello from 172.16.10.3 area 0 from Serial0/1/0 10.1.4.2 *Mar 23 01:18:42.199: OSPF: End of hello processing *Mar 23 01:18:45.519: OSPF: Rcv hello from 172.16.10.2 area 0 from Serial0/0/0 10.1.2.2 *Mar 23 01:18:45.519: OSPF: End of hello processing
The last debug command I’m going show you is the debug ip ospf adj command that will show us elections as they occur on broadcast and nonbroadcast multi-access networks: Router#debug ip ospf adj OSPF adjacency events debugging is on *Mar 23 01:24:34.823: OSPF: Interface FastEthernet0/1 going Down *Mar 23 01:24:34.823: OSPF: 172.16.10.1 address 10.1.1.1 on FastEthernet0/1 is dead, state DOWN *Mar 23 01:24:34.823: OSPF: Neighbor change Event on interface FastEthernet0/1 *Mar 23 01:24:34.823: OSPF: DR/BDR election on FastEthernet0/1 *Mar 23 01:24:34.823: OSPF: Elect BDR 0.0.0.0 *Mar 23 01:24:34.823: OSPF: Elect DR 0.0.0.0 *Mar 23 01:24:34.823: OSPF: Elect BDR 0.0.0.0 *Mar 23 01:24:34.823: OSPF: Elect DR 0.0.0.0 *Mar 23 01:24:34.823: DR: none BDR: none *Mar 23 01:24:34.823: OSPF: Flush network LSA immediately *Mar 23 01:24:34.823: OSPF: Remember old DR 172.16.10.1 (id) *Mar 23 01:24:35.323: OSPF: We are not DR to build Net Lsa for interface FastEthernet0/1