PAT in both directions
I need to do port address translation in both directions, so inbound and outbound SMTP use the same public IP. Address is 18.104.22.168 so I do an SNAT for port 25 from 22.214.171.124 to 10.1.1.1 and things are happy that way. Then do I just do a NAT for 10.1.1.1 to any external set the source to 126.96.36.199 and put that rule ahead of NAT 10.1.1.0/24 that sets the source to 188.8.131.52? It seems to work, but is there a way to limit it to just port 25 and not all ports for the outbound?