Connection verification to another pool

You should be able to populate a global array with client IP address when connected to Pool_1, then check the array when clients attempt connection on other vs with Pool_2, and discard if client IP is not in the array. This should get you started. You'll probably want to add some error checking and a method to clean up the array.

 virtual server 1 iRule (pool 1) 
when CLIENT_ACCEPTED {
   populate array with client IP address
  set ::pool1_clients([IP::client_addr])
  use pool 1
}
 virtual server 2 iRule (pool 2) 
when CLIENT_ACCEPTED {
   if { [info exists $::pool1_clients([IP::client_addr])] } {
     use pool 2
   } else { redirect "http://" }
}