Nat and port mapping on Win2K

[2651]

I want to set up a pop3 mail server from behind my NAT server and have hit a snag.

The story so far (sorry for length)...

I have set up NAT on my server so that all workstations can access the

http://WWW with

no problems. I hit trouble when I try to set up a mail server inside my private network.

My server has two NIC (internal 192.168.0.1/ external 203.174.157.171) and my e-mail server has the address 192.168.0.2 reserved via the Windows DHCP server. No problems there.

My DNS looks OK. All nslookups work (both internal and external. I can ping internal and most external I.P's without a hitch.

Now, I reserve the public address 203.174.157.170 for use with 192.168.0.2 through NAT/RRAS.

However, I am still unable to ping my mail server (mail.prospect-house.biz). From the e-mail server itself, when I ping, I get a response from the non-routable address (192.168.0.2) but not from the routable one. This is the same from all workstations.

Now, from the e-mail server I attempt to telnet to port25 on 203.174.157.170 and I have success. If I attempt this from any other server/workstation I get

H:\>TELNET 203.174.157.170 25
Connecting To 203.174.157.170...Could not open a connection to host on port 25 :
Connect failed.

Ping from main server shows
H:\>ping mail.prospect-house.biz

Pinging mail.prospect-house.biz [203.174.157.170] with 32 bytes of data:

Request timed out.

However, a ping from the e-mail server to mail.prospect-house.biz gives me a response on the 192.168.0.2 address only.


nslookup from both servers shows

H:\>nslookup mail.prospect-house.biz
Server: melias.prospect-house.biz
Address: 203.174.157.171

Name: mail.prospect-house.biz
Addresses: 203.174.157.170, 192.168.0.2

I'm at a loss with what to try next. Any help would be most appreciated