If dnsmasq dies, NetworkManager does not ensure that resolver configuration is coherent

[Steve Langasek]

Trying to debug an ipv6 resolution problem on my laptop, I killed the NM-spawned dnsmasq, expecting to relaunch it by hand with the same options. Instead, I found that immediately upon killing the process, /var/run/nm-dns-dnsmasq.conf was cleaned up from the filesystem. But /etc/resolv.conf was still pointed at 127.0.0.1.

Either NM should respawn dnsmasq when it's killed, or it needs to ensure the resolvconf hooks are called again to put /etc/resolv.conf into a coherent state.

Also, I'm not sure if it's related, but after doing this I found that the NM indicator was no longer letting me move between wireless networks or disconnect from the wireless; so I had to turn my antenna off and back on to get dnsmasq back.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: network-manager 0.9.4.0-0ubuntu4
ProcVersionSignature: Ubuntu 3.2.0-24.37-generic 3.2.14
Uname: Linux 3.2.0-24-generic x86_64
ApportVersion: 2.0.1-0ubuntu7
Architecture: amd64
CheckboxSubmission: 017452a27eca3c8b498abbfa5ef91db9
CheckboxSystem: ecaaad6fa1e0799a0aa1126bf620f39e
Date: Sat May 12 12:11:12 2012
InstallationMedia: Ubuntu 10.04.1 LTS "Lucid Lynx" - Release amd64 (20100816.1)
IpRoute:
 default via 192.168.0.1 dev wlan1 proto static
 169.254.0.0/16 dev wlan1 scope link metric 1000
 192.168.0.0/24 dev wlan1 proto kernel scope link src 192.168.0.6 metric 2
 192.168.122.0/24 dev virbr0 proto kernel scope link src 192.168.122.1
NetworkManager.state:
 [main]
 NetworkingEnabled=true
 WirelessEnabled=true
 WWANEnabled=true
ProcEnviron:
 TERM=xterm
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: network-manager
UpgradeStatus: Upgraded to precise on 2011-11-08 (185 days ago)
WifiSyslog:

nmcli-dev:
 DEVICE TYPE STATE DBUS-PATH
 wlan1 802-11-wireless connected /org/freedesktop/NetworkManager/Devices/2
 eth0 802-3-ethernet unavailable /org/freedesktop/NetworkManager/Devices/0
nmcli-nm:
 RUNNING VERSION STATE NET-ENABLED WIFI-HARDWARE WIFI WWAN-HARDWARE WWAN
 running 0.9.4.0 connected enabled enabled enabled enabled enabled

[chidalgo (chidalgo-gmail)]

I run into the same problem of dnsmasq respawning and dying.

As a test, i deactivate support for IPv6 (using Network Manager), and the problem disappers.

Can't find the problem right now, but smells like it's a bug related to IPv6 configuration.

BTW, i was running flawlessly IPv4 & IPv6 using previous Ubuntu versions.