APM Header Value in Data Group

Hi,

You should define an irule event instead and attach an irule to your Virtual Server. What you are trying to achieve is not permitted under the VPE. You can only use pure TCL scripting.

You can also define an irule that trap this header during the ACCESS_SESSION_STARTED event and save a value in a session variable that you will be able to reuse in the VPE :

when ACCESS_SESSION_STARTED { 
    if { [HTTP::header exists "S_NUM"] and [class match [HTTP::header "S_NUM"] equals WHITELIST] } {
        ACCESS::session data set "session.custom.snum" 1
    } else {
        ACCESS::session data set "session.custom.snum" 0
    }
}