[Pkg-utopia-maintainers] Bug#392813: [mzqrovna@0pointer.de: Stop! Wait!]

[Lennart Poettering]

On Sat, 14.10.06 16:15, Joey Hess (joey at kitenet.net) wrote:

> The problem in the context of Debian is that we're taking previously
> working systems that happen to search local, and breaking them by
> auto-enabling mdns. I agree that if a user has a working system that
> uses madns and adds "search local" to it, it's not a big deal when it
> starts being slow and/or breaking[1]. But this is a bit different, and
> seems to at least need to be fixed in the context of the Debian
> package.

I see the problem. Maybe the perl script should not touch
/etc/nsswitch.conf if it sees that mdns is already listed there or if
"search local" is included in /etc/resolv.conf. The latter check might
be useful in all cases because it is either a hint that the users has
a unicast-DNS domain called ".local" or that the user manually
configured nss-mdns in a way it suited him best. In both cases the
package shouldn't touch the user's configuration, I would argue.

> One option would be for the Debian package to warn about this at
> install/upgrade time, and either remove the search local, or remove the
> nsswitch.conf entries.

"Not touching" seems to be a better strategy in my eyes, if any of the
magic words are already found in the resolver configuration files.

BTW: to make "search .local" working properly would require hacking
the resolver itself. This is not possible with NSS modules alone,
unfortunately. Hacking the resolver is essentially patching the libc,
which is nothing I am so keen on. Apple did something like that for
MacOSX, but I am not convinced that this is really a good idea in the
first place. When I looked into this the last time I came to the
conclusion that doing this might offer a few advantages but also
creates a lot of disadvantages, which seem to overweight in my
eyes. (the major issue being that it makes it much more difficult to
disable the mDNS functionality, in addition it is kludgy by
definition, because the resolver semantics do not really match the mDNS
semantics.)

Lennart

-- 
Lennart Poettering; lennart [at] poettering [dot] net
ICQ# 11060553; GPG 0x1A015CC4; http://0pointer.net/lennart/