Comment 0 for bug 1003842

Revision history for this message
Thomas Hood (jdthood) wrote : Enabling dnsmasq by default breaks systems with non-equivalent upstream nameservers

A number of reports already filed against network-manager seem to reflect this problem, but to make things very clear I am opening a new report. Where appropriate I will mark other reports as duplicates of this one.

Consider a pre-Precise system with the following /etc/resolv.conf:

    nameserver 192.168.0.1
    nameserver 8.8.8.8

The first address is the address of a nameserver on the LAN that can resolve both private and public domain names. The second address is the address of a nameserver on the Internet that can resolve only public names.

This setup works fine because the GNU resolver always tries the first-listed address first.

Now the administrator upgrades to Precise and instead of writing the above to resolv.conf, NetworkManager writes

    server=192.168.0.1
    server=8.8.8.8

to /var/run/nm-dns-dnsmasq.conf and "nameserver 127.0.0.1" to resolv.conf. Resolution of private domain names is now broken because dnsmasq treats the two upstream nameservers as equals and uses the faster one, which could be 8.8.8.8.