F5 LTM VE 10.2.3: ip forward virtualserver

Yes, this is a simple one:

rule TCP_logging {
 when CLIENT_ACCEPTED {
  set remote [IP::remote_addr]:[TCP::remote_port]
  set vip [IP::local_addr]:[TCP::local_port]
  log "Rule TCP_logging fired, from $remote to vip $vip"
 }
}