I would like to get around the port 25 blocking by my ISP.
At my office, I have an existing NAT rule for private server to a public IP address, on port 25. For the same server I would like to NAT port 25 to 8025, but only for traffic to/from a specific IP address (home). On the home side, I'll have only 25>8025 for all traffic.
It will look like this:
Office Server(25) <> Cisco ASA(8025) <> Internet <> Home FW(8025) <> Home Server(25)
Office Server(25) <> Cisco ASA 5510(25) <> Internet <> Everyone Else(25)
This seemed like a simple matter. But I can’t add the 25>8025 NAT rule because it overlaps the existing 25>25 NAT rule.
Can this be done, or is it simply not possible?