Persistant balancing based on source IP

I looked some of the persistence profiles, like "source address" and they default to a 3-minute timeout. Which I take to mean if the user is idle for longer than 3-minutes, the next time they come in, they will get rebalanced.

 

 

I'm worried about upping that timeout for fear of eating up memory on the F5, forcing it to remember those sockets for hours.

 

 

Which is why I was hoping a rule or something could do a quick calculation on the IP and always come up with the same answer. That way the F5 would not need to remember the connection.

 

 

 

But, I hadn't looked at setting the expiration timer on a cookie insert. I'll try that first.

 

 

In case that fails for some reason and I have to fall back to some sort of source-address parsing - is there a way that can be done ?