Sendmail server alias problem

[Andrew Kaplan]

Hi there --

We have a sendmail server in operation and I noticed that an alias of the server does not appear to be working.

The server is known by two names, and when I do an nslookup of both names, the output indicates that both names appear to be configured on the internal network DNS servers. However, when I do the same using an external DNS server, the alias comes back as a non-authoritative record.

The problem that I am seeing is the following: If I send an e-mail to alias of the server from a remote host, the message does not get through. The message does get through if I am on the server itself.

I'm guessing the non-authoritative record on the external DNS server is causing this, but before I go there I wanted to know if there is something else I should check. Thanks.

[Ivan Ferreira]

>>> However, when I do the same using an external DNS server, the alias comes back as a non-authoritative record.

This is normal, a non authoritative record is just a record that was answered from a server that does not owns the zone, it's cached information.

Can you confirm in the /var/log/maillog that the mail reach the server?

[Andrew Kaplan]

Hi there --

I checked the maillog file, and there is no record of the message reaching the server.

[Ivan Ferreira]

From a remote host, do:

telnet alias_of_server.domain 25

Can you connect? Can you send an message using SMTP?

MAIL FROM: username@domain.com
RCPT TO: username@yourdomain.com
DATA:
Subject: Test
Test
.

[Andrew Kaplan]

Hi there --

I could not open a telnet connection to port 25 using the alias of host.

[Alexander Chuzhoy]

if you do "ping alias_of_mail_server"
do you get reply from the correct IP?

[Andrew Kaplan]

Ping won't work due to network security issues. A ping of the alias on the localhost returns the hostname and the correct address.

[Alexander Chuzhoy]

security issues?

Could it be that the required for communication ports are simply blocked by firewall and that's the reason why you can't access your mail server from remote?
Try to close the firewall and see if the problem dissapears.

[Andrew Kaplan]

Hi there --

I can access the webserver remotely via the hostname. It is only the alias that I am having problems with at this time.

[Andrew Kaplan]

Excuse me...I meant e-mail server. The server does have a web interface and I can access it using either the hostname or the alias. It is strictly the delivery of mail when using an e-mail address that inludes the alias that there is a problem.