Ubuntu Desktop does not show vagrant user in LightDM greeter

[courtarro]

I'm working on a desktop-based project, so I installed the ubuntu-desktop package on the Bento base box ubuntu-16.04. Because the vagrant user is set to UID 900, the Ubuntu Desktop login screen doesn't show it. Instead, only the Guest account is listed. To fix this issue, I had to edit /etc/login.defs to change the following two lines:

UID_MIN          1000
GID_MIN          1000

to:

UID_MIN           900
GID_MIN           900

At that point, both vagrant and vboxadd appear on the login screen. Is there any particular reason why the vagrant user is set to a UID of 900 instead of 1000 or higher? 1000 seems to be the de-facto minimum for interactive users on modern Ubuntu installs.

[cheeseplus]

Likely because these boxes are specifically targetted to be lightweight base boxes so we use server packages and generally assume there is no desktop.

[rickard-von-essen]

Please PR this. Since we allow login for the vagrant user it should be an interactive (normal) user.

[courtarro]

It seems like a cleaner solution is to update the UID of the vagrant user to be 1000 or higher (and the GID of the vagrant group), rather than drop the minimum UID. The vboxadd user, for instance, is UID 999, so it will show up with my workaround, which is not ideal.

I also don't know how my workaround will affect future updates (via Apt) to login.defs.

The change to the vagrant UID (perhaps to 1000) would be pretty simple to make. Each Debian and Ubuntu config has a preseed.cfg file that specifies:

d-i passwd/user-uid string 900

Unfortunately, this kind of change seems likely to cause problems with backward compatibility for everyone's provisioning scripts. I'm happy to submit a PR to make this change and continue discussions based on that.