Failover time

  • How long does/should it take for the backup to take over and route traffic?

    The backup becomes master quickly but it lags a couple of minutes before traffic starts to go through again.

    Is this a problem with the switch arp cache and the virtual IP changing it's MAC address?



  • The virtual IP has it's own MAC, so the arp cache shouldn't be a problem. Generally you see a few missed pings, but nothing near a couple of minutes. I've had heavily used systems switch to the backup without anyone noticing.

  • Failover will occur in under 5 seconds. Could be an issue with your switch where it won't allow the active CARP MAC on the other port until X minutes have passed. The MAC doesn't change, but a MAC moving from one port to another could be a problem depending on your switches and how they are configured.

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