http://avahi.org/wiki/AvahiAndUnicastDotLocal
https://ubuntuusertips.wordpress.com/2012/09/13/get-rid-of-avahi-service/
http://en.kioskea.net/faq/739-disabling-the-avahi-daemon
http://www.linux.org.ru/forum/admin/5055652
http://forum.ubuntu.ru/index.php?topic=200451.0

Edit the Avahi daemon config file:

% sudo vi /etc/init/avahi-daemon.conf
Search for the following lines, edit the line with “start on” and add “never and”:

-start on (filesystem and started dbus)
+start on (never and filesystem and started dbus)
stop on stopping dbus

One more thing to do in order to avoid the popup notice:
% sudo vi /etc/default/avahi-daemon
AVAHI_DAEMON_DETECT_LOCAL=0

To stop the daemon from the command line:
% sudo service avahi-daemon stop

And then, find out if it is really gone:
% ps -ef | grep -i [a]vahi
If you get no match, then it means that it is gone for good.


DNS and avahi:
/usr/lib/avahi/avahi-daemon-check-dns.sh