classic mode (v1)

[Mark Shuttleworth]

On 24/11/15 15:15, Gustavo Niemeyer wrote:
> Do we know which specific packages are broken and what causes these
> failures, so we can have a more clear idea of where the line between
> working and non-working is?

Martin gave sufficient warning about the behaviour of overlays that we
should pursue other courses of action.

> All of this to have a snap that works similar to every other snap, and
> takes no setup time the first time and every other time the snap is
> updated/reset.

The time involved is the same as that currently for LXD without a
snapshotting filesystem; it can be slow to write out 250MB on an rpi2,
but it's pretty fast on a laptop. And my expectation is that this is
one-time, with updates being handled normally for classic systems
thereafter.

>> It seems like we have the following options:
>>> 1) Once ubuntu-classic is installed the snap can never be updated, but
>>>    the *content* of the snap can be updated, i.e. you can keep your
>>>    classic environment up-to-date via "sudo apt full-upgrade" (or we
>>>    could even do it automatically via unattended-upgrades).
>> See above, dist-upgrading is not reliable, and it's rather fiddly to
>> fix the chroot after such a failure happened; this rules out
>> unattended-upgrades.
>>
> It'd be nice to understand what is broken there.

We've been using the overlayfs for a decade in the live-cd, I suspect
Pitti has a clear view on what works and what doesn't, and whether
upstream cares, or whether we've cared enough to fix it in the past too.

Mark