SMTP Connection Refused

[Robin Mordasiewicz]

On Wed, 2 Nov 2005, Ki Song wrote:

> However, when I send a message to a different e-mail server in house
> (store.knifecenter.com), it says the connection is refused. Here is the
> exact message that is returned in the postfix maillog:
>
> connect to store.knifecenter.com[70.88.225.6]: Connection refused (port 25)
> D7C9C3572A1: to=<listserv at store.knifecenter.com>, relay=none, delay=0,
> status=deferred (connect to store.knifecenter.com[70.88.225.6]: Connection
> refused)
> disconnect from unknown[10.1.10.19]
>
> What is going on? Any ideas?

It looks like you will either need to set up an SNAT on your firewall, or 
use a split DNS. The problem is that you are probably trying to connect to 
store.knifecenter.com, which is really a box in your DMZ or whatever, 
but the box on the inside is on a private LAN such as 10.1.10.20.

Telnet is your friend when troubleshooting mail servers.

ie.

telnet 10.1.10.19 25

you will then be able to issue commands directly to the mail server such 
as the following after a successfuly telnet to port 25 of the server.

helo mail.myserver.com
mail from: me at domain.com
rcpt to: listserv at store.knifecenter.com
data
this is a test
.