Comment 6 for bug 1284607

> Is dnsmasq getting its DNS server information from resolvconf,
> which in turn gets it from /etc/network/interfaces? Or, does
> dnsmasq take what it likes from /etc/network/interfaces directly,
> discarding the rest?

1. If you have only the dnsmasq-base and network-manager packages installed then a dnsmasq process is run as a slave of NetworkManager and gets its nameserver information exclusively from NetworkManager. This dnsmasq process provides name service exclusively at IP address 127.0.1.1.

2. If you have the "dnsmasq" package installed then a(nother) dnsmasq process is run independently of NetworkManager. By default this independent dnsmasq service is configured to obtain its nameserver information exclusively from resolvconf which in turn gets nameserver information from interface configuration processes including ifup, whose configuration file is /etc/network/interfaces.

The fact that you have no /etc/dnsmasq.conf strongly suggests that you do not have the "dnsmasq" package installed and so you fall into class #1.

Dnsmasq itself never looks in /etc/network/interfaces.

To understand how resolvconf works, please consult /usr/share/doc/resolvconf/README.gz .

To understand how Ubuntu uses NetworkManager, dnsmasq and resolvconf, please consult https://www.stgraber.org/2012/02/24/dns-in-ubuntu-12-04/ .