Okay, so here is the goal:
mail.domain.com is set as a public IP, let's say 1.1.1.1
Inside the network, I am using a Sonicwall appliance in front of an SME mail server.
What I want is for outside requests for 1.1.1.1 on port 25 to use NAT to send the traffic to the Sonicwall for spam/av filtering. When requests for 1.1.1.1 come in on port 80 or 443, I want NAT to send those to the SME server for webmail.
What I have done so far is gone into the ASDM and set up a Static Policy in NAT to map 1.1.1.1 to the Sonicwall. This works fine as long as I leave protocol on IP. When I try to change the protocol to TCP port 25, the NAT stops working.
I tried to leave the above rule using IP and then create a second one to NAT port 443 traffic on 1.1.1.1 to the SME server and then simply place that rule higher in importance than the other Static Policy, but, again, whenever I change protocol from IP to TCP 443, the NAT stops working completely.
Any ideas? As you can guess, I am not very well versed in PIX or using NAT in it.
Enable Port Address Translation
TCP
Original Port: 25
Translated Port: 25
You will have to have a rule for each service you want to use (25, 80, 443) even if two of the ports go to.