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localsystemuser

  • Dec 16, 2020
  • Joined Dec 15, 2020
  • 1 discussion
  • 2 posts
  • 0 best answers
  • Post posted... wait what?
  • In DNS stopped resolving after recent update

    diekuh How this could be a problem with network if all other devices in the network including docker containers running on this host have no DNS problem. Also test Ubuntu container works fine. If I exec to Postfix and manually change nameserver in /etc/resolv.conf to 1.1.1.1 it is able to resolve hostnames.

    • In DNS stopped resolving after recent update

      Hi,
      For some reason postfix-mailcow has stopped resolving DNS. It is not a firewall issue as I have disabled it also all other containers are able to resolve any hostname. Docker host is also able to resolve anything. My Docker network is set to 172.17.0.0 while my Mailcow network is 172.22.0.0. In unbound.conf 172.16.0.0/12 is allowed which includes both address spaces so this is not a case. I’ve tried to disable resolvconf running on the host but with no luck.

      Any idea what happened and how to fix that?

      A sample log from postfix:
      NOQUEUE: reject: RCPT from unknown[46.41.134.25]: 450 4.1.8 <adamkarski@marketingfirmy.com.pl>: Sender address rejected: Domain not found; from=<spamer@marketingfirmy.com.pl> to=<email@domain.com> proto=ESMTP helo=<marketinguj.pl>

      warning: dnsblog_query: lookup error for DNS query 25.134.41.46.dnsbl.sorbs.net: Host or domain name not found. Name service error for name=25.134.41.46.dnsbl.sorbs.net type=A: Host not found, try again

      root@mail:/opt/mailcow-dockerized# docker-compose exec postfix-mailcow curl wp.pl
curl: (6) Could not resolve host: wp.pl
root@mail:/opt/mailcow-dockerized# docker-compose exec dovecot-mailcow curl wp.pl
<html>
<head><title>301 Moved Permanently</title></head>
<body>
<center><h1>301 Moved Permanently</h1></center>
<hr><center>nginx</center>
</body>
</html>
root@mail:/opt/mailcow-dockerized# docker-compose exec clamd-mailcow curl wp.pl
<html>
<head><title>301 Moved Permanently</title></head>
<body>
<center><h1>301 Moved Permanently</h1></center>
<hr><center>nginx</center>
</body>
</html>