OSPF Becoming Neighbors, Hello parameters
Hello sent to 224.0.0.5
Timers by default:
- broadcast, point-to-point 10 sec
- nonbroadcast, point-to-multipoint 30 sec
5 Parameters for neighborship establishment
- Authentication
- same primary subnet (hellos are not sent on secondary subnets, though they can be advertised)
- same OSPF area type (regular, stab, not-so-stubby NSSA)
- no dup Router Id
- Hello and Dead timers equal
debug ip ospf hello
*Aug 7 01:58:21.395: OSPF-2 HELLO Fa0/0: Send hello to 224.0.0.5 area 0 from 192.168.12.1
R1#
*Aug 7 01:58:28.755: OSPF-2 HELLO Fa0/0: Rcv hello from 2.2.2.2 area 0 192.168.12.2
R1#
*Aug 7 01:58:30.923: OSPF-2 HELLO Fa0/0: Send hello to 224.0.0.5 area 0 from 192.168.12.1
R1#
*Aug 7 01:58:40.755: OSPF-2 HELLO Fa0/0: Send hello to 224.0.0.5 area 0 from 192.168.12.1
R1#
*Aug 7 01:58:49.775: OSPF-2 HELLO Fa0/0: Send hello to 224.0.0.5 area 0 from 192.168.12.1
R1#
*Aug 7 01:58:59.559: OSPF-2 HELLO Fa0/0: Send hello to 224.0.0.5 area 0 from 192.168.12.1
R1#show ip ospf neig
*Aug 7 01:59:08.759: %OSPF-5-ADJCHG: Process 2, Nbr 2.2.2.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
R1#show ip ospf neig
*Aug 7 01:59:09.351: OSPF-2 HELLO Fa0/0: Send hello to 224.0.0.5 area 0 from 192.168.12.1
R1#no debug ip ospf hello
*Aug 7 01:59:19.251: OSPF-2 HELLO Fa0/0: Send hello to 224.0.0.5 area 0 from 192.168.12.1