Conffiles and configuration management systems

[Raphael Hertzog]

On Tue, 04 May 2010, Soren Hansen wrote:
> Where this falls short is when you want to use a configuration
> management tool like Puppet. Puppet is a very flexible tool. You can use
> it to configure pretty much anything. This means that you can use it to
> change conffiles, and in turn this means that your upgrade experience is
> going to be very annoying: It will be riddled with questions about
> conffiles that you allegedly changed. Except, of course, you didn't.
> Puppet did it for you. Not only that, it often does it based on
> declarations of various sorts rather than just a straight copy of a file
> from a central store, so the exact changes may look foreign, even to the
> person who made the change in Puppet.

If you use puppet to manage some of your conffiles, why not stick
"force-confold" and "force-confdef" in /etc/dpkg/dpkg.cfg ?

That way the prompts are skipped... it assumes however that all modified
files are actively managed by puppet and keeping the old version is always
the right thing to do in that case.

> Add a capability to dpkg to let tools like puppet take over this conffile
> merging process. Or, the poor man's alternative: add a capability to
> dpkg to ignore specific conffiles.

That said I believe we want that kind of flexibility within dpkg but it
might require some larger changes than you expect. For this reason, I
would suggest to try to have a chat with Guillem Jover (main maintainer of
the C part of dpkg) before the UDS session.

There are also existing branches reworking the conffile handling done by
seanius(@debian.org) so you might want to discuss with him as well.

Unfortunately Guillem is hard to catch, he always has a backlog of stuff
to respond to. :(

On IRC, he's guillem or braindmg on #debian-dpkg at OFTC.

Cheers,
-- 
Raphaël Hertzog

Like what I do? Sponsor me: http://ouaza.com/wp/2010/01/05/5-years-of-freexian/
My Debian goals: http://ouaza.com/wp/2010/01/09/debian-related-goals-for-2010/