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Sergio000_19532's avatar
Sergio000_19532
Icon for Nimbostratus rankNimbostratus
Mar 27, 2018

HA order of precedence

Hi, community,

 

I have a doubt which is the order of precedence for failover. Because If I set various failover methods would will the one with the high preference, for example, if I configure VLAN failsafe, HA group and network failover which one will take precedence. If the VLAN that I use to monitor get down but the HA group is still with the high score what will happen? the device will go standby for the VLAN fail-safe or will be active because of the ha group. The same with network failover and HA group. Also, the HA group must be configured for all members of the data group in order to work?

 

application delivery
LTM

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  • jaikumar_f5's avatar
    jaikumar_f5
    Icon for MVP rankMVP
    Mar 27, 2018

    As far as I know, there is no precedence for a HA pair. It all depends on the HA table that is configured. But for HA Group, there is a score concept for failover.

    W.r.t to question if VLAN failsafe, HA group and network failover which one will take precedence ?

    The answer is, even if any of this fails, the failover will take place. It does not matter which goes out first. 

    tmsh show /sys ha-status

    If you go to the HA table, you will see an action inline to every features (VLAN failsafe,nic-failsafe,switchboard-failsafe etc...)

    You can refer article to know more about failover events.

    For HA-Group failover events doc.

  • Sergio000_19532's avatar
    Sergio000_19532
    Icon for Nimbostratus rankNimbostratus
    Mar 27, 2018

    Thank you for the answer, so if the network failover or VLAN fail safe its triggered and the HA group said that this device has the high score, this device will be in a loop of failing over between active and standby?

     

    The answer is, even if any of this fails, the failover will take place. It does not matter which goes out first.

     

    • jaikumar_f5's avatar
      jaikumar_f5
      Icon for MVP rankMVP
      Mar 27, 2018

      I stand corrected, my apologies.

       

      The HA group feature allows failover to occur based on changes to trunk health instead of on system or VLAN failure.

       

      So for HA Group failover, the other parameters does nt come into consideration. The device that has the best overall score at any given time becomes or remains the active device.

       

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