• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 597
  • Last Modified:

Sendmail problem: "mail loops back to me (MX problem?)"

Hi. Having a few problems.

I've got the MX records for a number of domains pointing to a single host, and on that host I've put the domains in /etc/sendmail.cf, ie:

Cw stub.org

I've also tried putting them in /etc/sendmail.cw, but that hasn't helped.

All the FAQs stop there, assuming that this will solve the problem, but it hasn't. I'm still getting mails to this domain (and others) bouncing with:

   ----- Transcript of session follows -----
553 www.vx-labs.org. config error: mail loops back to me (MX problem?)
554 <ade@stub.org>... Local configuration error

What else could be wrong? (Yes, I have restarted sendmail)

Thanks in advance

// Ade.
  • 2
1 Solution
adrianwardAuthor Commented:
Oo, I should mention some details:

Redhat Linux 6.0, hostname is root.vx-labs.org, running sendmail 8.9.3. The domain I'm trying to get working is stub.org

[root@root named]# cat /var/named/named.stub.org
@       IN      SOA     stub.org. root.vx-labs.org.  (
                                      2000021600 ; Serial
                                      28800      ; Refresh
                                      14400      ; Retry
                                      36000      ; Expire
                                      86400 )    ; Minimum
        IN      NS      ns.vx-labs.org.

        IN      MX      5 mail.vx-labs.org.

        IN      CNAME   www.vx-labs.org.
*       IN      CNAME   www.vx-labs.org.

Hope this helps a bit.


stub.org is expanded to www.vx-labs.org, and
www.vx-labs.org is not in the Cw statement,
hence the snafu.

My advice: don't use cnames for this stuff,
a straight A record - using the address of root.vx-labs.org - will work just the same,
and make this stuff easier to trace.

So basically: if you stick www.vx-labs.org in the cname, it'll work, but I would rather take www out of the picture altogether.
HTH & cheers,
adrianwardAuthor Commented:
Excellent, that's just it. Thanks.

I didn't realise that sendmail would look at the CNAME for the domain, I only thought it used the MX records.

It works perfectly now.

Featured Post

The new generation of project management tools

With monday.com’s project management tool, you can see what everyone on your team is working in a single glance. Its intuitive dashboards are customizable, so you can create systems that work for you.

  • 2
Tackle projects and never again get stuck behind a technical roadblock.
Join Now