Bug#392813: [Pkg-utopia-maintainers] Bug#392813: dns completely failed after upgrade to libnss-mdns 0.8-5

[Sjoerd Simons]

On Fri, Oct 13, 2006 at 07:35:36PM +0200, Walter Hofmann wrote:
> Package: libnss-mdns
> Version: 0.8-5
> Severity: normal
> 
> After today's Sid dist-upgrade, programs couldn't resolve names anymore.
> E.g. "ping www.google.com" fails with "ping: unknown host www.google.com".
> An strace of the failing ping is below.
> 
> I have never used libnss-mdns, but it was upgraded during the last
> dist-upgrade so it is suspect. I'm not sure why it is installed at all,
> I certainly never used it. I see that there is the following entry in
> /etc/nsswitch.conf:
>  hosts:          files mdns4_minimal [NOTFOUND=return] dns mdns4
> changing this entry to
>  hosts:          files dns
> made things work again.

Could you send the complete strace of ping -n www.google.com ? 

It's a little strange though. mdns4_minimal only tries to resolv hostnames
ending with .local and ip's in the link local range (169.254.0.0/16). So if you
ping google.com the following happens: 

 * first files is tried, which fails.
 * then mdns4_minimal is tried, which refuses to resolver the hostname as it
   doesn't end in .local (note the NOTFOUND=return option isn't taken)
 * then dns is tried, which should succeed and pings to google are sent :)
 * Only if dns _failed_ mdns4 is tried which tries to resolv the address on the
   local lan (which your strace shows)

For reverse resolving the same happens, only then mdns4_minimal refuses because
it's not in the right ip range. So the only way i can explain what your seeing
is that your dns failed in this case...

  Sjoerd
-- 
No matter where I go, the place is always called "here".