more fun with jsessionid persistence

Is anyone successfully doing this? From a tcpdump, here is what I am interpreting:

 

 

1) Client sends initial request

 

2) Server responds with JSESSIONID= cookie AND links with JSESSIONID= built in to URI

 

3) BIGIP evaluates

 

a) If cookie present, add persistence.

 

b) If no cookie present, lookup jsessionid in URI and add persistence

 

 

THe problem with both A & B is the persistence will be added on the 2nd load balancing decision, which may or may not be the original master server. This is easily solved with the cookie, as the persistence entry can be added on the HTTP_RESPONSE event. I'm struggling with the logic to :

 

 

1) On the response event, create persistence entry for cookie and URI

 

2) On the request event, if cookie persistence is used, delete the uri persistence entry and vice versa.

 

 

One follow-up. If you are setting both via uie persistence, and the value (jsessionid, either from cookie or link) is the same, does one get overwritten? I guess it doesn't matter, since the value will be matched when evaluted on the http_request event when persisted via the cookie value or the $jsess value.