point to different Pools w/ different persistence

I'm attempting to do the same thing, but it doesn't seem to be working reliably at all. The following iRule is specified within a persistence profile that is assigned as the Default Persistence Profile of a virtual server (logging statements were added for debugging purposes):

 

 

when HTTP_REQUEST {

 

if {[string tolower [HTTP::uri]] contains "tcgiservlet" } {

 

persist source_addr 255.255.255.255 120

 

log local0. " [IP::client_addr] - [HTTP::uri] - SOURCE persistence selected "

 

} else {

 

persist none

 

log local0. " [IP::client_addr] - [HTTP::uri] - NO persistence selected"

 

}

 

}

 

 

when LB_SELECTED {

 

log local0. " [IP::client_addr] - [HTTP::uri] - to node [LB::server]"

 

}

 

 

______________________________________

 

A sample of the logging that is produced is as follows:

 

 

Feb 22 14:07:38 tmm tmm[1036]: Rule XXXXXXXX_PERSIST : y.y.y.y - /live/servlet/GetLeastLoadedComponent?xxxxxx - NO persistence selected

 

Feb 22 14:07:38 tmm tmm[1036]: Rule XXXXXXXX_PERSIST : y.y.y.y - /live/servlet/GetLeastLoadedComponent?xxxxxx - to node POOLNAME-80 z.z.z.z 80

 

Feb 22 14:07:38 tmm tmm[1036]: Rule XXXXXXXX_PERSIST : y.y.y.y - /live/servlet/tcgiServlet - SOURCE persistence selected

 

Feb 22 14:07:38 tmm tmm[1036]: Rule XXXXXXXX_PERSIST : y.y.y.y - /live/servlet/tcgiServlet - SOURCE persistence selected

 

Feb 22 14:07:39 tmm tmm[1036]: Rule XXXXXXXX_PERSIST : y.y.y.y - /live/servlet/tcgiServlet - SOURCE persistence selected

 

Feb 22 14:07:39 tmm tmm[1036]: Rule XXXXXXXX_PERSIST : y.y.y.y - /live/servlet/tcgiServlet - to node POOLNAME-80 167.z.z.z 80

 

 

The problem is that the persistence doesn't seem to be taking effect immediately, as there will be several requests to one back-end node, and then all subsequent requests will go to the other back-end node. One thing I especially don't understand is the LB_SELECTED event only seems to trigger sporadically, and there doesn't seem to be any rhyme or reason to it. It doesn't occur for every request, but it occurs much more often than 120 seconds, which is the timeout value of the persistence.

 

 

Has anyone seen behavior like this or shed any light on what might be happening?