On Tue, Jul 16, 2019 at 11:44:12AM -0700, Ian Zimmerman via Exim-users wrote:
> On 2019-07-16 15:03, David Purton wrote:
> 
> >     2019-07-16 14:23:14 Start queue run: pid=12322 -qf
> >     2019-07-16 14:23:14 1hnFQ2-000379-9I no IP address found for host 
> > smtp.gmail.com
> >     2019-07-16 14:23:14 1hnFQ2-000379-9I == exam...@hotmail.com R=smarthost 
> > defer (-1): lookup failed for all hosts in smarthost router: 
> > host_find_failed=ignore host_all_ignored=defer
> >     2019-07-16 14:23:14 End queue run: pid=12322 -qf
> > 
> > But I can look up the domain normally on my machine:
> > 
> >     $ nslookup smtp.gmail.com
> >     Server:         8.8.8.8
> >     Address:        8.8.8.8#53
> > 
> >     Non-authoritative answer:
> >     smtp.gmail.com  canonical name = gmail-smtp-msa.l.google.com.
> >     Name:   gmail-smtp-msa.l.google.com
> >     Address: 74.125.24.109
> >     Name:   gmail-smtp-msa.l.google.com
> >     Address: 2404:6800:4003:c02::6d
> 
> nslookup does DNS protocol directly, while exim uses the system resolver
> library.  This is some kind of a clue.

Maybe, but the host command has no problems, and I assume telnet uses
the system resolver and that has no problems either.

> Since the machine is a laptop with intermittent connectivity, how is
> /etc/resolv.conf managed?  Does it always point to 8.8.8.8, or is there
> some hook in the scripts that bring wifi on/off line which can change
> the nameserver setting?  If yes does that hook work reliably, and
> quickly enough for the resolver to pick up the change when exim flushes
> the queue?

Network connectivity is controlled by NetworkManager and that sets the
contents of /etc/resolv.conf. I can keep running exim -qf as long as I
want and the DNS look up never seems to succeed no matter how long I've
been on the network.

> And since the machine is a laptop, you probably run systemd right?  Is
> systemd-resolvd active?  (Although I can't imagine how exim might end up
> talking to it.)

I do run systemd. But systemd-resolved is not active:

    $ systemctl status systemd-resolved
    ● systemd-resolved.service - Network Name Resolution
       Loaded: loaded (/lib/systemd/system/systemd-resolved.service; disabled; 
vendor preset: enable
      Drop-In: /usr/lib/systemd/system/systemd-resolved.service.d
               └─resolvconf.conf
       Active: inactive (dead)
         Docs: man:systemd-resolved.service(8)
               https://www.freedesktop.org/wiki/Software/systemd/resolved
               
https://www.freedesktop.org/wiki/Software/systemd/writing-network-configuration-manag
               
https://www.freedesktop.org/wiki/Software/systemd/writing-resolver-clients


David

-- 
David Purton
e: dcpur...@marshwiggle.net
m: 0413 626 862

-- 
## List details at https://lists.exim.org/mailman/listinfo/exim-users
## Exim details at http://www.exim.org/
## Please use the Wiki with this list - http://wiki.exim.org/

Reply via email to