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Forum Discussion

ingard's avatar
ingard
Icon for Nimbostratus rankNimbostratus
May 02, 2017

Reselect a specific backend based on initial response

Hi I'm trying to select a different backend and retry the same request based on the response from the initially selected backend. Basically the backend will either serve the request itself or respond...
devops
iRules
LTM
JG's avatar
JG
Icon for Cumulonimbus rankCumulonimbus
May 04, 2017

OK see two modified events:

when CLIENT_ACCEPTED {
    set retries 0
    set re-selected 0
    set debug 5
}

when LB_SELECTED {
    if { $re-selected == 1 } {
        set re-selected 0
        return;
    }

    if { $retries == 0 } {
         Log LB pool/server selection
        if { $debug > 0 } { log local0. "Retries : $retries - Server Selected : [LB::server pool] [LB::server addr]:[LB::server port]" }
    } else {
         Reselect LB node if retries > 0
        if { $debug > 0 } { log local0. "Retries : $retries. wanted host/port = $wantedhost / $wantedport" }
        set re-selected 1
        LB::reselect pool pool_media_transcoding $wantedhost $wantedport

         Log LB pool/server selection
        if { $debug > 0 } { log local0. "Retries : $retries - Server Selected : [LB::server pool] [LB::server addr]:[LB::server port]" }
    }
    if { $debug > 4 } { log local0. "LB_SELECTED - Retries : $retries - Request: $request" }
}