Because Router-id conflict led business exception.

Publication Date:  2013-12-31 Views:  216 Downloads:  0
Issue Description
Topology:
Client---internal network -----S9300-1----C7606-----DCN network-----Server
Between the S9300 and C7606 interact via OSPF routing,  and packet dropped  after switchover.
Alarm Information
null
Handling Process
Since the ping without the business  source address to server is normal, there is no proven link quality problem.

And  the problem should still be out on the routings.

And when  check ospf error found Duplicate ack continues to grow, then I think this cutover Router-id has changed, the original is the interface address , now turned into a loopback address, suspected router-id routing oscillation caused by the conflict, replaced Router-id testing business back to normal, and delete loopback address, found also PING, to prove the existence of an address conflict issues;
Root Cause
1, VRRP double masters or  problems caused by  MSTP abnormalities;
2, IP address conflicts ;
3, other issues;
Suggestions
null

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