Comment 24 for bug 327362

Documented at <https://wiki.ubuntu.com/JauntyJackalope/ReleaseNotes#Avahi will not start if a .local domain is present>:

The avahi-daemon package, which implements the mDNS "zeroconf" standard, includes a check to avoid running when a conflicting .local DNS domain is present. It is reported that some ISPs advertise such a .local domain on their networks, which will leave Ubuntu 9.04 hosts unable to see names advertised on the local network (327362).

To force the use of mDNS on a network configured this way, users can run the command:

sudo sed -i -e'/AVAHI_DAEMON_DETECT_LOCAL/s/1/0/' /etc/default/avahi-daemon