Run the
Show OSPF Neighbors test on the required Edge. Following is an example of the test output:
Verify the following in the output:
Verify if the state of neighbor is Full/(DR or BDR). If this state is not seen, then there is issue with OSPF neighbors' convergence.
Down state, Attempt/Init state would be seen if you have sent/received OSPF hello packet. If the neighbor is in this state for too long, verify the Area ID, Neighbor ID, Router ID, and OSPF configuration.
If it is stuck between 2-way state or Ext start state, verify the MTU issues.
RxmtL is LSA retransmission list. This value is used when retransmitting Database Description and Link State Request packets. The default value is 5 seconds. If you see any values, then there is DBD packet exchange issue in transit. It should not be too high ideally. Verify transit path.