howl, mdns, mdnsresponder and libnss-mdns

[Erik Bågfors]

Hi.

This is a tip for home users who have their own small network and also
a question about  what the ubuntu guys are planing when it comes to
these things.

For those of you who are unfamiliar with mdns (multicasting dns) it's
simply a way for each computer on a network bo announce who they are,
what ip they have and what they can do.

For example, at home I have 5 machines.
One running ubuntu hoary
Two running ubuntu warty
One running Suse 9.1 (haven't switched it over to ubuntu yet :) )
One running MacOSX.

All computers (except one) is running a dynamic dhcp which means that
they might have a new IP tomorrow. But thanks to the wounders of mdns
they can always find eachother with "hostname.local".  This makes my
life sooooo much easier. Even if one computer changes ip all the
others will still find it with "hostname.local". It saves me from
having to set up static ip's and either seting up a local dns server
or modifying /etc/hosts on all computers.

So, to set this up, this is what I had to do.
on the hoary box:
sudo apt-get install libnss-mdns mdnsresponder
edit /etc/nsswitch.conf and add "mdns4" to the line starting with "hosts:"

On the warty box
sudo apt-get install mdnsresponder
build my own package of libnss-mdns and install it
edit /etc/nsswitch.conf in the same way

On the Suse box
install mdnsresponder (I grabbed the binary from my warty system. It
seams to work) and run it.
Suse can automatically lookup the .local domain.

On the MacOS box.
Nothing, this is all by default.

Apart from this the boxes can also annonce what they can do. My mythtv
box is now announcing that it has mythtweb running and from a mac
running safari it can be found automatically.

Now on to what ubuntu is doing? I think that Jeff is the debian
maintainer of howl? Will this ever be supported out of the box in
ubuntu? Is there any security issues with this? It seams like anyone
could bring a computer into my network and hijack any of my hostnames,
that's not a good thing.

But it's still VERY VERY usable for me.  I would love it if ubuntu at
least would do what Suse has done, and be able to resolve the .local
domain out of the box.


Regards,
Erik