Limit connections to nodes

Hi CB

I did have a look at that one, though I don't think default limits will work as described, as they want to be able to hand off to a specific server or "downpage" once the node limit is reached.

I essentially need a way to track NODE connections and limit, regardless of VIP connection numbers.

I managed to find this off a older post (http://devcentral.f5.com/Default.aspx?tabid=53&forumid=5&tpage=1&view=topic&postid=702612287), though it only tracks VIP connections, and I have the same problem as the poster had, where it has issues with timed-out connections going over the limit.

  
 when RULE_INIT { 
 set ::total_active_clients 0 
 set ::max_active_clients 1 
 log local0. "rule session_limit initialized: total/max: $::total_active_clients/$::max_active_clients" 
 } 
 when CLIENT_ACCEPTED { 
 log local0. "Client accepted" 
 log local0. "active clients $::total_active_clients" 
 } 
 when HTTP_REQUEST { 
 log local0. "current active clients $::total_active_clients" 
 ; test cookie presence 
 if {[HTTP::cookie exists "ClientID"]} { 
 log local0. "active user with cookie making http request" 
 set need_cookie 0 
 set client_id [HTTP::cookie "ClientID"] 
 ; if cookie not present & connection limit not reached, set up client_id 
 } else { 
 if {$::total_active_clients < $::max_active_clients} { 
 log local0. "http request from new client access granted. cookie set."  
 set need_cookie 1 
 set client_id [format "%08d" [expr { int(100000000 * rand()) }]] 
 log local0. "current active clients $::total_active_clients" 
 log local0. "new active client" 
 incr ::total_active_clients 
 log local0. "current active clients $::total_active_clients" 
 ; otherwise redirect 
 } else { 
 log local0. "http request from non active connection denied" 
 HTTP::redirect "http://www.google.com" 
 incr ::total_active_clients 
 log local0. "attempting to close connection" 
 catch HTTP::close 
 catch TCP::close 
 return 
 } 
 } 
 } 
 when HTTP_RESPONSE { 
 ; insert cookie if needed 
 if {$need_cookie == 1} { 
 HTTP::cookie insert name "ClientID" value $client_id 
 } 
 } 
 when CLIENT_CLOSED { 
 ; decrement current connection counter for this client_id 
 log local0. "current active clients $::total_active_clients" 
 log local0. "client closed" 
 log local0. [IP::remote_addr] 
 if {$::total_active_clients > 0} { 
 log local0. "decremeting active clients" 
 incr ::total_active_clients -1 
 } 
 log local0. "current active clients 
 $::total_active_clients" 
 }