[Pkg-utopia-maintainers] Bug#929010: Bug#929010: Bug#929010: avahi-daemon: /etc/network/if-post-down.d/avahi-daemon is slow on eth0

[Vincent Lefevre]

On 2019-05-16 17:52:03 +0200, Michael Biebl wrote:
> I would suggest the following: If there is a local nameserver but no
> network connectivity, query the local nameserver only.

OK, I can do that. Indeed, the default behavior of "host" is to try
every server in /etc/resolv.conf until it succeeds. I suppose that
the solution would be to use this option:

  -s
      Do not send the query to the next nameserver if any server responds
      with a SERVFAIL response, which is the reverse of normal stub
      resolver behavior.

I have another question: in

  if ! $(egrep -q "nameserver 127.0.0.1|::1" /etc/resolv.conf); then 

why testing 127.0.0.1 only, and not all local nameservers?
For instance, 127.0.1.1 is used by NetworkManager:

https://askubuntu.com/questions/627899/nameserver-127-0-1-1-in-resolv-conf-wont-go-away

Also, the regexp should be something like "^ *nameserver +(127.0.0.1|::1)"
or "^ *nameserver +(127\.|::1)", i.e.
  * one should make sure that it is a nameserver line (in particular,
    not a comment);
  * several space characters should match;
  * one should make sure that ::1 is preceded by "nameserver"
    (the parentheses are missing).

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Vincent Lefèvre <vincent at vinc17.net> - Web: <https://www.vinc17.net/>
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