1

On a client machine, I run the following command:

while true ; do ping -c 1 server_name.local. ; sleep 1s ; done

It outputs:

ping: unknown host server_name.local.

...except that when I reboot the server, there are a few successful pings just before shutdown and again right after startup.

Likewise, the diagnostic utility mdns-scan only sees the server while it is rebooting.

What's going on, and how can I make it work more consistently?

The server is running Ubuntu Desktop 11.10.

I found the following message in the /var/log/syslog. But it should be noted that .local seems to work fine for other devices on my network.

Avahi detected that your currently configured local DNS server serves
a domain .local. This is inherently incompatible with Avahi and thus
Avahi disabled itself. If you want to use Avahi in this network, please
contact your administrator and convince him to use a different DNS domain,
since .local should be used exclusively for Zeroconf technology.
For more information, see http://avahi.org/wiki/AvahiAndUnicastDotLocal
Brent Bradburn
  • 2,766
  • 2
  • 29
  • 35
  • Note: I later found that it was working briefly every time I restarted the networking (not just at boot). – Brent Bradburn Dec 03 '15 at 06:19
  • After a couple more reboots for both the client *and* the server, everything seems to be working correctly. But I haven't identified the underlying source of the problem. I think it is very useful to document that this sort of problem is likely solvable by manually starting the avahi daemon as noted in my answer. – Brent Bradburn Dec 03 '15 at 07:37
  • Closed for end-of-life? Just because Canonical doesn't want to maintain software in perpetuity, AskUbuntu has to leave users high-and-dry as well? – Brent Bradburn Jan 06 '16 at 21:05
  • Apparently I am the only person in the world who is affected by this. Nevertheless, I use numerous Ubuntu devices with a variety of versions. Some of these devices would be completely senseless to upgrade. Perhaps I should figure out what on my network is causing this problem, but thankfully, AskUbuntu has this quick-and-dirty workaround posted -- which seems to work with all of the versions of Ubuntu that I require. – Brent Bradburn Feb 03 '17 at 21:25
  • Maybe post it here: https://retrocomputing.stackexchange.com/ – Brent Bradburn Aug 17 '19 at 23:38

1 Answers1

1

A bug report at https://lists.ubuntu.com/archives/foundations-bugs/2012-December/129282.html hints at the following workaround alternatives:

  • sudo start avahi-daemon -- this would need to be done after every boot
  • modify /etc/default/avahi-daemon (or similar) with AVAHI_DAEMON_DETECT_LOCAL=0
Brent Bradburn
  • 2,766
  • 2
  • 29
  • 35
  • Note: `avahi-daemon` might be needed on both the client and the server. If it has shut itself down on either, you could have name resolution problems. I have seen mixed results related to this, but I found that starting the daemon was necessary on at least one of my clients. Strangely, another client showed the same "inherently incompatible" message -- but nevertheless the daemon was left running and was publishing that machine's name. – Brent Bradburn Dec 03 '15 at 06:46
  • Also of note: I don't have the foggiest idea why avahi thinks that there is a problem with my local DNS server -- which I assume is my NetGear router. – Brent Bradburn Dec 03 '15 at 06:50