console-conf fails on Ubuntu Core when a snap is pre-seeded that creates a system user

[Oliver Grawert]

more details can be found at:

https://forum.snapcraft.io/t/pre-seeding-a-snap-that-creates-a-system-user-breaks-console-conf/15432

It is now possible to pre-seed lxd in Ubuntu Core images, when doing that an lxd user is created in the extrausers database during the lxd installation on first boot (before console-conf starts).

Having a user exist prior to console-conf seems to make it fail to create the actual SSO user later.

[Oliver Grawert (ogra)]

potentially caused by "snap create-user", so adding a snapd bug task for now (please close if wrong)

[Samuele Pedroni (pedronis)]

This needs to be debugged in practice, I don't see code in snapds that tracks external user to make decisions, managed vs not is decided based on internal user concepts.

[Zygmunt Krynicki (zyga)]

I think someone who knows console-conf should have a look at what is going on. It might help to provide some references as to how to get an image with LXD and how to boot it in qemu to reproduce the problem.

[Oliver Grawert (ogra)]

pre-seeding can be done by adding lxd to required-snaps: in the model assertion and the following bit to the gadget.yaml of the gadget in use to have "lxd init" run during startup:

https://paste.ubuntu.com/p/tGQvgVFSkR/