I'm having DNS resolution issues in various contexts which appear to trace back to my networking configuration.
I'm running just the dnsmasq-base
installation of dnsmasq
on two Linux installations (Lubuntu 12.04 and 12.10). I haven't done anything in particular to configure dnsmasq
, but I think some other changes I made previously may have lead to an incorrect configuration when upgrading.
The working configuration on machine 'A' running 12.04 sets /etc/resolv.conf
to use 127.0.1.1 (which in /etc/hosts
is set to $HOSTNAME
) On machine 'B' where certain applications such as OpenVPN experience DNS resolution issues, /etc/resolv.conf
is set to 192.168.1.1, which is my gateway IP. Only certain applications are affected. Web-browsing, for example, works just fine.
Any idea if this difference is the cause of the DNS resolution issues, and why 'B' is behaving differently?
Edits:
Both 'A' and 'B' are running dnsmasq
, both are using DHCP to get DNS configuration, and I'm only using dnsmasq for DNS.
There is no /etc/dnsmasq.conf
file. I understand that this is normal when running just dnsmasq-base
.
The contents of /etc/resolvconf
on the two machines appear to be identical. No extraneous/missing files.
Sorry I can't be more specific about the nature of the problem. "DNS resolution issue" was the end-point of my discussion with technical support at my VPN provider.
Best Answer
On machine B, if
/etc/NetworkManager/NetworkManager.conf
containsdns=dnsmasq
thenresolv.conf
should contain only one "nameserver" line, namelynameserver 127.0.1.1
. 127.0.1.1 is the address where the NetworkManager-controlled local forwarding nameserver listens. NetworkManager gives that nameserver forwarding addresses to use.Try running
sudo dpkg-reconfigure resolvconf
on machine B. This will restore the needed symbolic link from/etc/resolv.conf
to../run/resolvconf/resolv.conf
.Are you running a third-party VPN client? Such clients are known to clobber
/etc/resolv.conf
and not to restore it when they exit. You may have to dosudo dpkg-reconfigure resolvconf
every time you stop such a client.Another thing to try is: comment out
dns=dnsmasq
in/etc/NetworkManager/NetworkManager.conf
and then reboot. This disables the NetworkManager-controlled local forwarding nameserver which has some known issues.