How to control the count of the session by iRule ?

The persistence records are removed when the pool member is marked down by a service check. However, exceeding a connection limit should not result in marking the pool member down. What service checks are you using? Is the pool member actually failing? Maybe your server returns a 500 status code when it's above a certain concurrency limit?

 

 

I don't understand your question about cookie persistence. You are correct. Cookie persistence does not make use of the session persistence table.