Weblogic: Universal vs Source Address Persistence

Hi Mr.Shaggy,

Regarding Question 1:

The difference of the two persistence method is just the "input data" that is used to track the persistence session table information. Source_IP persistence will always use the SRC_IP of the connecting client to create a session table entry, where as universal persistence can use any client provided data as "input data" (this could be the SRC_IP too, but in most cases the the session cookie of your application will be used to track the client). The benefit of using the application cookie as "input data" is, that the client can freely roam between different ISPs without loosing its session and you can even load balance multiple client behind a single proxy server.

Regarding Question 2:

SRC_IP and also Universal Persistence will always honor the persistence records as long as the persistence records are not timed out, the persisted pool members are not offline or the "input data" hasn't changed somehow (e.g. different SRC_IP or different application cookie). There are also some edge-cases, which may cause the F5 to send the request to the wrong pool member, if you mix multiple persistence methods on a single clientside TCP connection pointing to the same pool member. The edge case will happen in the cause you don't use a OneConnect Profile on your Virtual Server. In this case the F5 will always balance just the initial HTTP-Request destined to a given pool. So if you change the persistence method of an already established end-to-end connection (e.g. using an iRule that applies different persistence methods based on the requested URI) this may have no effect if the outcome of the new persistence method will result in a selection of a different pool member (see SOL7964 for further information). Beside of more or less common edge-case previously noted, also the advanced persistence settings "Match Across Services", "Match Across Virtual Servers" and "Match Across Pools" may also cause the F5 to change the persisted pool members under certain conditions...

Cheers, Kai