Forum Discussion
NimbostratusIRule to Limit *Real* User Connections to VIP
Working with Big-IP 4200 (v11.3) and want to be able to identify actual user count (not connections) and apply a limit to a VIP. Any user exceeding the limit would be served some HTML.
I've seen various ways of doing this, but most are based on connection limits and don't really reflect the 'real' world.
4 Replies
- Kevin_Stewart
Employee
So how are you defining "actual user count"? The number of requests per user? Number of open sessions/browsers? Or are you talking about total number of actual users accessing the application (vs. TCP connections)?
- nitass
are these helpful?
HTTP session limit by hamish at travellingkiwi.com
https://devcentral.f5.com/wiki/irules.HTTP_Session_Limit.ashxCodeShare Refresh: HTTP Session Limit by Colin Walker
https://devcentral.f5.com/articles/codeshare-refresh-http-session-limit.Uh8ZbG0-ZQI 
Alan_Taylor_122Thanks for the examples, Nitass. They look to be a good place to start.
Kevin, thanks for the response - I am talking about the total number of actual users accessing the application (vs. TCP connections).
- Kevin_Stewart
Both examples are actually pretty close I think to what you want then. The idea is that, because HTTP is a stateless protocol, you first need a state mechanism for the client to identify itself across requests - a cookie. You then need a tracking mechanism on the server side to correlate all of the clients, based on their cookie "IDs", into a countable structure - the session table. That does not preclude a single user from opening up multiple browsers, getting separate cookies, and consuming multiple sessions - unless you can add something else to the state reference like a source IP address.
