Bug#846944: Installing libnss-resolve before libnss-mdns breaks mDNS name resolution

[Felipe Sateler]

On 13 January 2017 at 18:24, Michael Biebl <biebl at debian.org> wrote:
>>>> libnss-mymachines - nss module to resolve hostnames for local container instances
>>
>> This is meant to be after files but before resolve (so the same position
>> as libnss-docker and libnss-gw-name). Are you deliberately installing it with
>> a lower priority than upstream's recommendation?
>
> We'll have to look into this. This change was made by Felipe in
> 7da95fd9f9a2330ffd3132c6673b25f929a78f09 for #789006. Maybe it was
> unintentional for mymachines (the original bug report was for myhostname)
>
> Felipe, can you chime in here?


This was the upstream recommendation at the time. That was changed in
upstream commit 9053aaad4255a1d01a50f8e44784cd7eebe8f95c , with the
following log message:

    man: change recommended order of NSS modules in /etc/nsswitch.conf

    So far we recommended placing "nss-mymachines" after "nss-resolve"
in the order
    of preference in /etc/nsswitch.conf. This change reverse this
order.

    Rationale: single-label names are resolved via LLMNR by resolved,
which has to
    time out if no peer by that name exists. By placing
"nss-mymachines" first
    (which always responds immediately) we avoid running into this
timeout for most
    containers. Both modules should return the same data if LLMNR is
used by the
    container anyway.

    While we are at it, improve the man pages of the three NSS modules
in other
    ways a bit.


So I guess we just failed to update usage with upstream?

-- 

Saludos,
Felipe Sateler