Comment 33 for bug 923685

On Sat, Feb 11, 2012 at 08:16:57PM -0000, Thomas Hood wrote:
> Here's the next iteration of the proposal.

> 1) /etc/resolv.conf contains no nameserver information => exit
> 2) "Generated by NetworkManager" in /etc/resolv.conf => exit
> 3) /etc/network/interfaces contains "mapping" or "source" lines => append

A 'mapping' stanza should have no effect at all on whether we append.

If a 'source' stanza exists at all, it most likely points to other interface
definitions that *do* provide resolver info, so why would we want to append
in that case except as a last resort? I.e., I think this also collapses
into the fallback case 6).

> 4) /etc/network/interfaces contains a logical interface definition with
> name N and configuration method name "dhcp" and the file also contains an
> "auto N" line => exit
> 5) /etc/network/interfaces contains a logical interface definition with
> name N and a "dns-nameservers" option and the file also contains an "auto
> N" line => exit

The plan I discussed with Stéphane explicitly does *not* require the auto
line for either of these. The reasoning is that there is already an
interface definition which we know will overwrite the resolver info in some
cases, so /etc/resolv.conf is *not* static. If the admin assumed it was
static, then they've made a judgement error; resolvconf is merely exposing
this error, not causing a bug in its own right.

> 6) Append

So I think that, modulo the dropping of 3) ifquery, the earlier proposal
from Stéphane is still what we want to go with.