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collinz1_17223's avatar
collinz1_17223
Icon for Nimbostratus rankNimbostratus
Jan 18, 2011

iRule using findstr in TCP payload

I am trying to create an irule that will search the TCP response from a server for the userData: value and them persist based on that. The irule is below, which i have associated with a Universal persistence profile, but when i try to initiate a connection, no connection is being established to one of the load balanced servers. If i remove the persistence profile i am load balanced fine:

 

 

when SERVER_CONNECTED {

 

TCP::collect 1500

 

}

 

when SERVER_DATA {

 

set usrid [findstr [TCP::payload] "userData:" 9]

 

if {$usrid ne ""} {

 

persist uie $usrid

 

}

 

}

 

 

application delivery
dev
devops
iRules

2 Replies

  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Jan 18, 2011
    Are you sure the failure is that no serverside connection is attempted or established? The iRule shouldn't take any effect until then.

     

     

    Can you add TCP::release to SERVER_DATA and retest?

     

     

    http://devcentral.f5.com/wiki/default.aspx/iRules/tcp__release

     

     

    Aaron
  • collinz1_17223's avatar
    collinz1_17223
    Icon for Nimbostratus rankNimbostratus
    Jan 19, 2011
    It appears that if i reduce the TCP::collect value, i get connected. However i only get connected if i set the value to 19 or below:

     

     

    TCP::collect 19

     

     

     

    Which is fine as far as connecting goes, however i guess this means that the irule is only collecting 19 bytes of data, which isn't enough to find my search string.