Testing 50 servers

I actually wrote an iRule for this exact purpose. You have to make sure and have DNS working properly. This article in support will help with that: https://support.f5.com/kb/en-us/solutions/public/5000/200/sol5299.html.

Basically my rule uses DNS to process a URI for the string "server=server1.domain.com" and then takes the server name and does a DNS lookup and then connects to that single node. If "server=" is not in the URI string then it just moves on to whatever rule or pool you have balancing your normal traffic. This way you can monitor every server individualy for application functionality. The rule is below:

 
 when CLIENT_ACCEPTED { 
 set debug 1 
 set servername "localhost"  
 } 
  
 when HTTP_REQUEST { 
 set uri [string tolower [HTTP::uri] ] 
 if { $uri contains "server=" } { 
 set servername [findstr $uri "server=" 7 "&"] 
 if {$servername != "localhost"} { 
 HTTP::collect 
 NAME::lookup $servername 
 } else { 
 } 
 } 
 } 
  
 when NAME_RESOLVED { 
 set serverip [NAME::response] 
 if {$debug ==1 } { 
 log local0. "$servername IP address is $serverip"} 
 if {$servername != "localhost" } { 
 if { [catch {node $serverip [TCP::local_port] } ] } { 
 persist source_addr 60 
 log local0. "ERROR: attempting to assign to node $servername: $serverip" 
 } 
 } 
 HTTP::release 
 }