Session persistence - reading application set cookie

I've re-enabled all 6 servers in the pool and tried the following irule, copied from Hoolio's post in https://devcentral.f5.com/Community/GroupDetails/tabid/1082223/asg/39/aft/33490/showtab/groupforums/Default.aspx

 

 

This seems to be working but to be honest irules aren't my strong point and I dont know why it's working.

 

Is anyone able to give a break down

 

 

of the following, in particular what the set lbsicap section does

 

 

 

when HTTP_REQUEST {

 

cookie length is greater than 0

 

if { [string length [HTTP::cookie "AUTHTOKEN"]] > 0 } {

 

persist uie [HTTP::cookie "AUTHTOKEN"]

 

} else {

 

set lbsicap [findstr [HTTP::uri] "AUTHTOKEN" 11 ";"]

 

if { $lbsicap != "" } {

 

persist uie $lbsicap

 

}

 

}

 

}

 

when HTTP_RESPONSE {

 

if { [string length [HTTP::cookie "AUTHTOKEN"]] > 0} {

 

persist add uie [HTTP::cookie "AUTHTOKEN"]

 

}

 

}

 

 

 

Thanks