I've been configuring a bigip to live behind a load balancer using the direct server return method. It 'should' be a pretty straight forward configuration and is pretty widely used.
there is one configuration detail that I was stuck on for a bit. there is a db key that needs to be disabled.
[root@bigip:Active] config # b db | grep Connection.AutoLasthop
Connection.AutoLasthop = disable
if this key is enabled, the switch will send the response packets back to the last hop in the pool. which, in this case, is my direct server return load balancer.
Appearantly, this is an *easy* catch when using the GUI. It's what I get for using CLI.