Name resolution based on source IP

Can one use this code share in the following mannor?

 

In regards to using the LTM as a reverse proxy could the iRule be used to determine the destination that gets applied to the pool in a VIP?

 

An example, an internal server does file transfer to an ip that is a VIP on the external LTM. The LTM then is triggered by the iRule mentioned above, does a lookup to resolve the actual destination ip address and sends the traffic outbound.

 

 

Is it fair to say, a static name like update.sun.com would be applied to the iRule mentioned in the code share, when the response is received the destination is then set.

 

 

If this is the case would you have to configure all possible replies as members of a pool? Or would the response from the dns lookup result in being set as the destination?