Do I need avahi?

[Marko Vojinovic]

On Sun, 28 Jul 2013 16:21:55 +0200
lee <lee at yun.yagibdah.de> wrote:
> Marko Vojinovic <vvmarko at gmail.com> writes:
> > On Sun, 28 Jul 2013 00:58:24 +0200
> > lee <lee at yun.yagibdah.de> wrote:
> >> Hmm I disabled it now and will see what happens.  There are 224
> >> packages depending on the avahi package --- that's insane for
> >> something that isn't needed.
> >> 
> >> Why are there so many packages depending on it?
> >
> > Not on my system (F18/64bit/KDE), there are only 22 of them
> > depending on avahi, and most of them are just wine-related. If I
> > didn't need wine or nss-mdns, I could remove it no problem:
> >
> > So it's just nss-mdns and wine & friends.
> 
> It would even remove imagemagick, emacs, vlc, ddd, fvwm, the NVIDIA
> drivers and a lot of other packages I need.

Ok, for your convenience, I have uninstalled avahi (temporarily)
from my machine (remember, this is F18 over here). Here you go:

[root at Yoda ~]# yum list avahi imagemagick emacs vlc ddd fvwm
Loaded plugins: langpacks, presto
Installed Packages
ImageMagick.x86_64     6.7.7.5-3.fc18      @fedora                
ddd.x86_64             3.3.12-11.fc18      @fedora                
emacs.x86_64           1:24.2-19.fc18      @updates               
fvwm.x86_64            2.6.5-3.fc18        @fedora                
vlc.x86_64             2.0.7-1.fc18        @rpmfusion-free-updates
Available Packages
ImageMagick.i686       6.7.7.5-3.fc18      fedora                 
avahi.i686             0.6.31-6.fc18       fedora                 
avahi.x86_64           0.6.31-6.fc18       fedora                 
[root at Yoda ~]# uname -a
Linux Yoda 3.9.11-200.fc18.x86_64 #1 SMP Mon Jul 22 21:04:50 UTC 2013
x86_64 x86_64 x86_64 GNU/Linux

As you can see, none of the packages you have mentioned actually
depends on avahi. Also, I have Intel graphics here so it doesn't make
much sense to try to install nvidia drivers, but I can bet that they do
not depend on avahi either.

> > OTOH, if you are running, say, Gnome3 or such, then you should ask
> > the relevant developers on the relevant mailing list why oh why do
> > they depend on avahi so much. ;-)
> 
> I don't --- I could ask on the fvwm mailing list if fvwm needs avahi,
> and I bet it doesn't.
> 
> Perhaps yum has messed up the dependencies?

What appears to be happening in your case is that avahi is needed by
the Gnome3 desktop environment, maybe even by gdm login manager.
Removing avahi then probably removes the whole Gnome stuff along,
leaving the machine without a DE and without a login manager. And then
it probably turns out that the packages you have mentioned depend on
the presence of some DE on the system (vlc being a typical example).
Given that DE would be removed, most of that GUI stuff would go with it.

That's my guess-theory. If you care to provide the actual yum output
for "yum remove avahi", someone might figure it out more precisely than
that.

Or it might be that F19 has some weird changes introduced compared to
F18. But I guess it would be mentioned in the release notes or
somewhere...

HTH, :-)
Marko