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WWT_BIGIP_99228's avatar
WWT_BIGIP_99228
Icon for Nimbostratus rankNimbostratus
Sep 05, 2012

IRule Question about Backend Nodes

Dev Central,

 

I know that I can find out what backend server I am persisted to if I have a persistence profile associated with the Virtual Server however when I dont have persistence enabled which is the case for over 3/4 of my 300 or so Virtual Servers how can I tell what backened server I am being sent to for a given request. Is there some kind of IRule magic that I could write in order to log this or figure out this information?

 

Thanks,

 

WWTBIGIP

 

application delivery
dev
devops
iRules

2 Replies

  • Richard__Harlan's avatar
    Richard__Harlan
    Historic F5 Account
    Sep 05, 2012
    You can run the LB::server command to return the current selected server.

     

     

    You can log with with the following command

     

     

    log local0. "Server = LB::server Virtual = [virtual name]"
  • Michael_Yates's avatar
    Michael_Yates
    Icon for Nimbostratus rankNimbostratus
    Sep 05, 2012
    I also released a Tech Tip and a Tool that I created that will allow you to take the BIGIP Cookie and unhash it tell you where you are connected.

     

     

    Note: It will not work if you have the cookie encrypted and you should use the method that Richard Harlan pointed out.

     

     

    Cookie Persistence and Troubleshooting

     

     

    Hope this helps.