21-2 debug ip ospf events

Syntax Description:

This command has no arguments.

Purpose: To display information regarding OSPF events such as the forming of adjacencies, Hello packets, LSA flooding, Designated Router (DR) selection, and shortest path first (SPF) calculations. If an OSPF neighbor relationship is not being formed between two routers, then this command can be used to determine the problem.

Example 1: Displaying the Successful Formation of an OSPF Adjacency

The following is representative output from the debug ip ospf events EXEC command for a successful configuration. The EXEC command clear ip ospf process is used to clear the existing adjacency.

 r6#  debug ip ospf events  OSPF events debugging is on r6#  clear ip ospf process  Reset ALL OSPF processes? [no]:  yes  r6# 6w4d: OSPF: Rcv hello from 1.1.1.1 area 7 from Serial0/1 10.1.1.18 6w4d: OSPF: 2 Way Communication to 1.1.1.1 on Serial0/1,  state 2WAY  6w4d: OSPF: Send DBD to 1.1.1.1 on Serial0/1 seq 0x22BC opt 0x42 flag 0x7 len 32 6w4d: OSPF: End of hello processing 6w4d: OSPF: Rcv DBD from 1.1.1.1 on Serial0/1 seq 0x1D6E opt 0x2 flag 0x7 len 32   mtu 1500  state EXSTART  6w4d: OSPF: First DBD and we are not SLAVE 6w4d: OSPF: Rcv DBD from 1.1.1.1 on Serial0/1 seq 0x22BC opt 0x2 flag 0x2 len 27 2  mtu 1500 state EXSTART 6w4d: OSPF: NBR Negotiation Done. We are the MASTER 6w4d: OSPF: Send DBD to 1.1.1.1 on Serial0/1 seq 0x22BD opt 0x42 flag 0x3 len 52 6w4d: OSPF: Database request to 1.1.1.1 6w4d: OSPF: sent LS REQ packet to 10.1.1.18, length 144 6w4d: OSPF: Rcv DBD from 1.1.1.1 on Serial0/1 seq 0x22BD opt 0x2 flag 0x0 len 32   mtu 1500  state EXCHANGE  6w4d: OSPF: Send DBD to 1.1.1.1 on Serial0/1 seq 0x22BE opt 0x42 flag 0x1 len 32 6w4d: OSPF: Rcv DBD from 1.1.1.1 on Serial0/1 seq 0x22BE opt 0x2 flag 0x0 len 32   mtu 1500 state EXCHANGE 6w4d: OSPF: Exchange Done with 1.1.1.1 on Serial0/1 6w4d: OSPF: Synchronized with 1.1.1.1 on Serial0/1,  state FULL  6w4d: %OSPF-5-ADJCHG: Process 1, Nbr 1.1.1.1 on Serial0/1 from LOADING to FULL, Loading Done 

Example 2: Debugging an OSPF Adjacency Problem

The following is representative output from the debug ip ospf events EXEC command when there is a mismatch in the dead interval.

 r6#  debug ip ospf events  OSPF events debugging is onr6# 6w4d: OSPF: Rcv hello from 1.1.1.1 area 7 from Serial0/1 10.1.1.18 6w4d: OSPF: Mismatched hello parameters from 10.1.1.18 6w4d: OSPF:  Dead R 40 C 123  , Hello R 10 C 10 

R is the received dead interval time and C is the dead interval time configured on the local router.