Ubuntu
network-manager package

  1. Bug #1048430
  2. Comment #29

Comment 29 for bug 1048430

Revision history for this message
gberche (guillaume-berche) wrote :

I had a similar issue after upgrading from 15.04 to 15.10 yesterday

I was loosing DNS resolution ramdomly few minutes after VM start

Mar 18 10:27:17 guillaume-box NetworkManager[885]: <info> DNS: starting dnsmasq...
Mar 18 10:27:17 guillaume-box NetworkManager[885]: <warn> dnsmasq not available on the bus, can't update servers.
Mar 18 10:27:17 guillaume-box NetworkManager[885]: <error> [1458293237.010557] [dns-manager/nm-dns-dnsmasq.c:387] update(): dnsmasq owner not found on bus: Could not get owner of name 'org.freedesktop.NetworkManager.dnsmasq': no such name
Mar 18 10:27:17 guillaume-box NetworkManager[885]: <warn> DNS: plugin dnsmasq update failed
Mar 18 10:27:17 guillaume-box NetworkManager[885]: <info> Writing DNS information to /sbin/resolvconf
[...]
Mar 18 10:27:17 guillaume-box dnsmasq[965]: DBus support enabled: connected to system bus
Mar 18 10:27:17 guillaume-box dnsmasq[965]: warning: no upstream servers configured

I was observing, dnsmaq process indeed running but not consistently resolving name requests. I was observing empty dnsmasq conf files:

guillaume@guillaume-box:/etc/NetworkManager/dnsmasq.d$ ls -al
total 8
drwxr-xr-x 2 root root 4096 avril 17 2015 .
drwxr-xr-x 7 root root 4096 mars 17 23:11 ..
guillaume@guillaume-box:/etc/NetworkManager/dnsmasq.d$ ls -al /var/run/NetworkManager/dnsmasq.conf
-rw-r--r-- 1 root root 0 mars 18 10:27 /var/run/NetworkManager/dnsmasq.conf

Whereas the network manager was properly displaying the DHCP provided DNS servers in the its UI.

Trying to turn off and on network in the network manager did not solve the issue.

I ended up turning off dnsmasq by eding /etc/NetworkManager/NetworkManager.conf and comment out the following line from
    dns=dnsmasq (as suggested into http://www.ubuntugeek.com/how-to-disable-dnsmasq-in-ubuntu-12-04precise.html)

This seems to have worked around the issue. I understand the limitation of the workaround (disabling dnsmasq) is that I don't have anymore a local DNS cache, and only the 1st respondind DNS server is queried for address resolution.

I ran into a reported bug (sorry I lost its reference) that claimed this to be a distribution upgrade problem, and was suggesting to uninstall dsnmaq and reinstall it. I haven't tried yet.

Hope this helps narrowing this nasty bug which was quite time consuming to me.