iRule to assign node based on URI, bypassing source IP persistence

Hello,

We are using a standard VS to load balance HTTPS traffic to 2 web servers, using source IP persistence. For a particular statistics application we need to bypass load balancing and persistence and send the HTTPS traffic to the 2nd web server.

I customized this iRule to catch the URI /stats/stats.js and send to a pool containing only the 2nd server :

when HTTP_REQUEST {
  if { [string tolower [HTTP::uri]] starts_with "/stats/" } {
       pool stats.https.pool
       }
    else {
       pool website.https.pool
       }
  }

The default condition seems to work fine as all URI's are working. But on the /stats/stats.js URI I get permanently 404's.

According to a logging iRule I'm using I see that regular traffic is sent to either one or the other web servers, and the /stats/ traffic to the 2nd one only... But I still get 404's. Also CURL from the BIG-IP shows that the URL is accessible on the destination server.

I tried to add 'persist none' before the pool assignment but that didn't help.

Any advise would be strongly appreciated ! I'm sure this is a basic problem but I don't get it right now 🙂

Cheers,

Gerald