Amahi DNS not working

Amahi has proven itself to me as a solid and reliable home server solution. However, occasionally, I’ve had a problem where DNS stops working, sometimes after OS updates have been installed and the server restarted. It’s only happened 2 times over the last year or two, and the helpful Amahi folks on the IRC channel came to the rescue both times, but I’d thought I’d document the solution here.

Sympton: You use the Amahi network troubleshooter, and find you can’t ping hda from your hda box, i.e. name resolution is not working.

Solution 1: If you are running a desktop version of linux, or have installed some specific packages, like Jenkins, that install libvirtd service, then you need to disable that service. Unfortunately libvirtd takes the default DNS port and therefore Amahi, which uses dnsmasq, can’t work. This is documented here, and the solution is to use:

sudo systemctl disable libvirtd
sudo reboot

Solution 2: If you can now ping hda, but still can’t ping www.google.com, it means the DNS provider that amahi uses for the web is not reachable. Amahi support multiple DNS providers: OpenDNS, OpenNIC and Google Public DNS. Mine was set to OpenDNS, which I think is the default, the solution was to change it to Google DNS.

If you haven’t tried Amahi, and you have a home network with a bunch of computers, I highly recommend checking it out!