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I've been having an issue to send mails, mostly to domains using as mailserver.

For example:

Jul  5 15:38:20 vm-dns-mail postfix/smtp[29249]: B6A3A20113E: to=<>, relay=none, delay=189023, delays=189019/0.05/4/0, dsn=4.4.3, status=deferred (Host or domain name not found. Name service error for type=AAAA: Host not found, try again)

But it has a correct MX record:

vm-dns-mail ~/bin # dig mx
;; ANSWER SECTION:        7362    IN      MX      5

And I can telnet to it:

vm-dns-mail ~/bin # telnet 25
Connected to
Escape character is '^]'.
220 Microsoft ESMTP MAIL Service ready at Fri, 5 Jul 2013 19:45:12 +0000 Hello []
250-SIZE 157286400

I thought it was an IPV6 issue, as this VM is unable to connect to IPV6. So I added this line to

inet_protocols = ipv4

But it merely changed the issue to this:

Jul  5 21:41:38 vm-dns-mail postfix/smtp[30661]: C1102201234: to=<>, relay=none, delay=2, delays=0.01/0/2/0, dsn=4.4.3, status=deferred (Host or domain name not found. Name service error for type=A: Host not found, try again)

What could cause this, rather annoying, problem?

share|improve this question
seems like a name resolution issue, check your DNS resolver on that machine. – topdog Jul 5 '13 at 19:54
I was actually just looking into that, and something rather stupid seems to have fixed it... "options timeout:1 attempts:1" in resolv.conf – Tuinslak Jul 5 '13 at 20:01
up vote 1 down vote accepted

This is what resolv.conf looked like in Postfix's chroot.

vm-dns-mail /var/spool/postfix/etc # cat resolv.conf 
options timeout:1 attempts:1

Removing options timeout:1 attempts:1 seems to have fixed it. Keeping that line, but adding other DNS servers (opendns for example) seems to also fix it...

I'll keep running some tests and monitor it.

share|improve this answer
You are using Google's nameservers. If you are running a mailserver, it's better to set up your own nameserver on your system. – edwardmp Jul 5 '13 at 22:48
What would be the difference ? – Tuinslak Jul 6 '13 at 7:29
Most DNS based services have daily query limits meaning that if you use Google's name servers you will get locked out. The second issue is do you want this creepy company spying on your mail traffic as well ? – topdog Dec 31 '13 at 18:00

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