Bill Cole:
> On 26 Jul 2018, at 11:23, Alex wrote:
>
> > I have a postfix-3.3.1 running on a fedora28 system and frequently see
> > warnings such as these in my logs:
> >
> > Jul 26 10:42:09 mail03 postfix/dnsblog[3949]: warning: dnsblog_query:
> > lookup error for DNS query 51.225.249.24.b.barracudacentral.org: Host
> > or domain name not found. Name service error for
> > name=51.225.249.24.b.barracudacentral.org type=A: Host not found, try
> > again
>
> This is a potentially misleading error message due to a postfix/resolver
> quirk. It DOES NOT mean that "51.225.249.24.b.barracudacentral.org"
> resulted in a NXDOMAIN, it means that an A record for a name server for
> the parent domain could not be found. A completed resolution with a
> NXDOMAIN result is silent.
Actually, the error message means that there was no DNS reply: no
A record, no NXDOMAIN, etc., therefore Postfix cannot know whether
the A record exists.
Wietse
