name or service not known

[rdavisids]

I have now moved everything from our sendmail server to the development Zimbra server. I am now getting emails back from several domains that have in the return message.

Reporting-MTA: dns; mailhost.intdoc.com
X-Postfix-Queue-ID: BE7C150457F
X-Postfix-Sender: rfc822; sysop@intdoc.com
Arrival-Date: Wed, 1 Mar 2006 18:20:57 -0600 (CST)

Final-Recipient: rfc822; lzollinger@casham.com
Action: failed
Status: 5.0.0
Diagnostic-Code: X-Postfix; casham.com: Name or service not known

The domains listed are "real."

Where should I start? I looked for similar problems on the forums but didn't see anything that fit. I have used Sendmail but am not familiar with Postfix.

I am using 3.01 (160) on RHES 4

[rdavisids]

Well I've found my problem. Postfix needed the relay host for our Postini mail servers to complete the deal.

Sorry.

[jesse]

That solution is more of a workaround IMO.

Here is the problem:

If you are trying to send mail from Zimbra to a domain which doesn't have an A record associated with it, it will fail. It doesn't matter if it has MX records or not.

> [root@mail log]# nslookup
> casham.com
Server: 10.92.1.1
Address: 10.92.1.1#53

Non-authoritative answer:
*** Can't find casham.com: No answer
> set querytype=mx
> casham.com
Server: 10.92.1.1
Address: 10.92.1.1#53

Non-authoritative answer:
casham.com mail exchanger = 100 casham.com.mail1.psmtp.com.
casham.com mail exchanger = 200 casham.com.mail2.psmtp.com.
casham.com mail exchanger = 300 casham.com.mail3.psmtp.com.
casham.com mail exchanger = 400 casham.com.mail4.psmtp.com.
casham.com mail exchanger = 500 mail.casham.com.

I am experiencing the same problem with the same type of nameserver responses from u.washington.edu.

Thank you.

BTW.. I used the same workaround, but I'm using a mail server which I'm trying to retire.

-Jesse

[jesse]

I turned on DNS lookups and this problem went away.