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).
--
Vincent Lefèvre <vinc...@vinc17.net> - Web: <https://www.vinc17.net/>
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Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)
