How to control the count of the session by iRule ?

The customer site should use the session cookie for client session connecting

 

They can not use source address because source address has Proxy and NAT problems.(When group of client IP address is same)

 

So, Customer must use Insert Cookie Persistence.

 

 

Test 1. Using simple persistence and connect limit on pool member. (Service check is http)

 

 

When connections on the pool member reach the limit, status on pool member is yellow color and then unavailable.

 

At that time, the pool member in persistence records delete. And then, client can not connect the same web server.

 

 

Test 2. Using Cookie persistence and connect limit on pool member. (Service check is http)

 

 

When connections on the pool member reach the limit, status on pool member is also yellow color and then unavailable.

 

Also client can not connect the same web server.

 

 

Test 3. Using Cookie persistence and connection limit on virtual server. (Service check is http)

 

 

When I use connection limit on virtual server, the BIG-IP do not receive new session and existing session.

 

 

That`s why, the existing session is disconnected when user already established session. (because http session is very short time.)

 

 

 

So, I need the iRule.

 

 

Something like this.....

 

So, If the count of the session is over 1000, I don`t want to receive new session. but the existing session still connect.

 

 

And If the count of the session is under 800, I want to receive new session.

 

 

How to make the iRule ?