APM Session Variables fail to update in cache

Here is a workaround I have used in the past.

Add this iRule to the Virtual Server...

when ACCESS_POLICY_AGENT_EVENT {
  if { [ACCESS::policy agent_id] eq "my_dns_lookup" } {
    if { [ACCESS::session data get session.my_loop_counter] eq "1" } {
      set hostname [ACCESS::session data get session.logon.last.MyHostDestination]
      ACCESS::session data set session.HostIP_1 [RESOLV::lookup @10.10.10.10 -a $hostname]
      set found [ACCESS::session data get session.HostIP_1]
      log local0. "Host: $hostname ...and what we found:$found ."
    } elseif { [ACCESS::session data get session.my_loop_counter] eq "2" } {
      set hostname [ACCESS::session data get session.logon.last.MyHostDestination]
      ACCESS::session data set session.HostIP_2 [RESOLV::lookup @10.10.10.10 -a $hostname]
      set found [ACCESS::session data get session.HostIP_2]
      log local0. "Host: $hostname ...and what we found:$found ."
    } elseif { [ACCESS::session data get session.my_loop_counter] eq "3" } {
      set hostname [ACCESS::session data get session.logon.last.MyHostDestination]
      ACCESS::session data set session.HostIP_3 [RESOLV::lookup @10.10.10.10 -a $hostname]
      set found [ACCESS::session data get session.HostIP_3]
      log local0. "Host: $hostname ...and what we found:$found ."
    }
  }
}

In the VPE...

1. Create a new Variable Assign Object at the beginning of the policy (before the macro)

   Name: my_loop_counter initial
   Assignment: session.my_loop_counter = Text 0
   

2. Create a new Variable Assign Object after the form where they enter the hostname.

   Name: my_loop_counter_assign
   Assignment: session.my_loop_counter = expr { [mcget {session.my_loop_counter}] + 1 }
   

3. Create a new Variable Assign Object after the iRule Event Object (you will need to use the ID "my_dns_lookup" for the iRule Event Agent).

   Name: Variable Assign
   Assignment:
      session.HostIP = if { [mcget {session.my_loop_counter}] eq "1" }
                         { expr { [mcget {session.HostIP_1}] }
                       } elseif { [mcget {session.my_loop_counter}] eq "2" }
                         { expr { [mcget {session.HostIP_2}] }
                       } elseif { [mcget {session.my_loop_counter}] eq "3" }
                         { expr { [mcget {session.HostIP_3}] }
                       }
   

You will then need to do your session.HostIP check later in the VPE.

I hope this helps you get this configured.

-Seth