fallback to different VIP in Irule??

If you want to select a second VIP to handle the request when a new request is parsed and the default pool is down, you can use something like:

 
 when HTTP_REQUEST { 
  
     Check if currently selected pool has no active members 
    if {[active_members [LB::server pool]] == 0}{ 
  
        Use the fallback VIP 
       virtual fallback_vip 
    } 
 } 
 

Of for lower overhead, you could change from the HTTP_REQUEST to the CLIENT_ACCEPTED event. Then the check would only be done when a client establishes a new TCP connection to the VIP versus on each HTTP request.

Aaron