Nexus vPC convergence time & failover time question

[chaejungho]

Nexus vPC convergence & failover time question.

●Topology

Q1> vPC Keep-alive failure, vpc status and traffic loss occurs a few seconds?

Q2> vPC Keep-alive after a failed reconnect, vpc status and traffic loss occurs a few seconds?

Q3> vPC Peer-link failure, vpc status and traffic loss occurs a few seconds?

Q4>vPC Peer-link after a failed reconnect, vpc status and traffic loss occurs a few seconds?

Q5> vPC Keep-alive+Peer-link Dual failure, vpc status and traffic loss occurs a few seconds?

Q6>vPC Keep-alive+Peer-link after a Dual failed reconnect, vpc status and traffic loss occurs a few seconds?

I really curious. Help.

[Madhukrishnan Gopinathan Nair]

Q1> vPC Keep-alive failure, vpc status and traffic loss occurs a few seconds?

  It does not impact VPC as long as VPC peer-link is up.

Q2> vPC Keep-alive after a failed reconnect, vpc status and traffic loss occurs a few seconds?

 No change or impact

Q3> vPC Peer-link failure, vpc status and traffic loss occurs a few seconds?

    VPC secondary link will disable the vpc ports in order to prevent any loops. May expect very very short disruption for the active flows. 

Q4>vPC Peer-link after a failed reconnect, vpc status and traffic loss occurs a few seconds?

  VPC on secondary peer will come up and I do not except any major impact. Again since port-channel hashing changes may experience minor disrution but may not be visible.

Q5> vPC Keep-alive+Peer-link Dual failure, vpc status and traffic loss occurs a few seconds?

This will have an impact on the traffic flows. This causes split brain (both switches thinks peer is down). 

Q6>vPC Keep-alive+Peer-link after a Dual failed reconnect, vpc status and traffic loss occurs a few seconds?

I thinks this recovers your worst case scenario :)

Hope this helps and rate the post if found useful.

Thanks,

Madhu

[chaejungho]

Thank you for answers.

Please add question.

Q4>vPC Peer-link after a failed reconnect, vpc status and traffic loss occurs a few seconds?

       VPC on secondary peer will come up and I do not except any major impact. Again since

       port- channel hashing changes may experience minor disrution but may not be visible.

      vpc role change will occur born?

Q5> vPC Keep-alive+Peer-link Dual failure, vpc status and traffic loss occurs a few seconds?

        This will have an impact on the traffic flows. This causes split brain (both switches thinks peer is down). 

        Dual failure.
        The auto-recovery operation.
        Standby vpc peer->Active operation change into a master? (Dual active)

Q6>vPC Keep-alive+Peer-link after a Dual failed reconnect, vpc status and traffic loss occurs a few seconds?

       I thinks this recovers your worst case scenario :)

        Hope this helps and rate the post if found useful.

       The auto-recovery operation.

       vpc role change will occur born? traffic loss?

[chaejungho]

Do you perform auto-recovery even if you perform shutdown / no shutdown operation via CLI in questions 5 and 6?