Bug#812574: grub-pc: wants to overwrite admin configuration on each upgrade

[Colin Watson]

On Mon, Jan 02, 2017 at 12:37:32PM +0100, Thorsten Glaser wrote:
> On Sat, 31 Dec 2016, Colin Watson wrote:
> > The current postinst is certainly trying to use ucf in such a way, so
> > let's try to debug this.  Please could you:
> 
> Oh ok. Let me check that this system is affected first…

Thanks, and sorry for once again taking a while to get round to this.

> >  * attach /var/lib/ucf/cache/:etc:default:grub
> >  * attach /etc/default/grub
> 
> Attached.
> 
> >  * show the output of "grep /etc/default/grub /var/lib/ucf/hashfile"
> 
> tglase at tglase:~ $ grep /etc/default/grub /var/lib/ucf/hashfile
> fe09266a730fcba271f832ebb82a6a91  /etc/default/grub
> 
> > With any luck that will be enough to make some progress here.
> 
> OK, thanks!

Unfortunately, when I put these in place in a VM, I couldn't reproduce
your bug; and the information here looks right, in that the hash in
/var/lib/ucf/hashfile matches the hash of
/var/lib/ucf/cache/:etc:default:grub.  There must be something a bit
more subtle happening, or else I'm being stupid.

I guess we need to break out bigger guns.  Could you do the same
package-reinstall procedure as before, only this time:

 * temporarily edit /usr/bin/ucf, changing its initialisation from:

     DEBUG=0
     VERBOSE=''

   to:

     DEBUG=1
     VERBOSE=1

 * export DEBCONF_DEBUG=developer in the environment

That should let me see both what ucf is doing and (enough of) what the
GRUB postinst is doing.

Thanks,

-- 
Colin Watson                                       [cjwatson at debian.org]