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Thursday, December 3, 2009

6509 VSS failover issues

We have configured a 6509 VSS to test our failover scenarios. There is a primary and a secondary switch for backup purposes. To simulate the testing, first we shut down the primary switch and we noticed that all the traffic that is going through secondary switch. Then we restarted the primary switch. But now we observe that the secondary switch is restarting all the ports. Its takes 50 sec to come back resulting in a down time. Any pointers to what issue could be? We user BFD for dual active detection.

Debugging steps
  1. Delete priority and preemption, save your config and test again
  2. Remove priority and preemption
  3. Make sure to SAVE the config
  4. Now reboot again and test
In a scenario where you do not have priority and preemption, if you reboot both switches at the same time, switch-1 will always be the primary and switch-2 is the back up where you don't have access to make any config changes.

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  1. Question - to configure bfd, I created 2 separate networks, say and for each interface, say 1/2/48 and 2/2/48. Then I have eigrp running. Then I start seeing eigrp-ipv4 errors that the neighbor interfaces are not on a common subnet for that physical interface in the logs.
    If I make those interface passive interface under eigrp, will it interfere with how bfd works?

  2. Hi Iris,

    Unfortunately I don't have the answer to your question. But we do have Cisco certified experts who will be able to help you. Can you try post your question at application. The link is below.



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