This question was already posted on the product specific forum and reported here for reaching a wider audience.
We are evaluating pfSense as a cheap multi wan load balancer and traffic shaper. We have a separate firewall behind pfSense and no plan to substitute it and integrate its functionality in pfSense itself. I read that "connections are routed over each WAN in a round-robin manner." . This can cause problems with https connections for example and we are experimenting problems with a legacy ftp remote server too.
The documentation I found suggests to force specific traffic on a WAN or enable sticky connections The first approach is an unacceptable compromise with load balancing. The second is not applicable to our system because the real lan, as hinted before, is behind another firewall, so all requests come from the same client ip and pfSense would use only one WAN.
What we would need is probably what was already asked here and received no answer.
Is it possible to use sticky connections based on destination address instead of source address ? What alternative ways can be try to solve the connections problems related to the round robin routing ?