UIDs of data-owning users might change between deployed images

[Clint Byrum]

We had a rather confusing situation recently while doing image based updates in Helion:

* Create cloud using image without ceilometer
- time passes
* Create new image _with_ ceilometer

On the controllers, data was stored in /mnt as the UID for _cinder_, let's say 1001.

In the new image, because ceilometer ended up getting created before cinder, it took UID 1001 in the new /etc/passwd. On rebuild/reboot, /mnt/state/var/lib/cinder was owned by 1001, which was ceilometer, but cinder was running as 'cinder' which was now 1002.

So, we must have a static registry of user names to UID's, and a guard against this sort of problem turning up undetected. We will need to backup /etc/passwd to /mnt/state and verify that the new image has the same mappings for all existing users. If not, we should go into a failure state so that an admin can rollback or deploy a new compatible image.

[Clint Byrum (clint-fewbar)]

Image based updates seem less important to us now. It still will be a problem that needs solving, but for now we can side-step it by updating servers in-place.

Also unassigning myself as I won't have time to work on it.

[Steven Hardy (shardy)]

This bug was reported against an old version of TripleO, and may no longer be valid.

Since it was reported before the start of the liberty cycle (and our oldest stable
branch is stable/liberty), I'm marking this incomplete.

Please reopen this (change the status from incomplete) if the bug is still valid
on a current supported (stable/liberty, stable/mitaka or trunk) version of TripleO,
thanks!

[Launchpad Janitor (janitor)]

[Expired for tripleo because there has been no activity for 60 days.]