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dimka___104021's avatar
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Dec 02, 2009

override source address persistency




I've pretty simple VS on BigIP 9.4.7 with source address affinity glued to this VS. Default backend has 3 backend server.


Sourece address persistency is working correctly. But if one backend dies, client reqeusts still sent to dead backend. Persistency record exists in persistency table until it timeouts.


How can i send client requests to alive backend, instead of dead one?

5 Replies

  • Hi Dimka,



    If a pool member is marked down by a monitor, it should be removed from load balancing whether there there is a current persistence record or not. Is the monitor marking the pool member down when it dies?



  • Hi Dimka,


    Are you monitoring the backend server using the LTMs Monitor?



  • Hi,



    Yes, i have same http monitor assigned to all pool members.


    Strange thing is, in web GUI i see pool member marked red (status down), but client requests are still sent to this backend server.


    If i remove persistency record from pers.table, new requests are sent to available backend server. Seems, that if there're persistency record, but pool member is down, traffic still goes to backend.


    Any ways to override persistency with iRule?



  • Yes, it's possible to check the persistence record and the corresponding pool member to see if it's not up and disable the persistence. But I think it would be better to figure out why the default functionality doesn't seem to be working. The quickest way to do this would probable to be open a case with F5 Support. They'll be able to review a tech.out, traces and possibly debug from an iRule to help determine why this isn't working as expected.