Bug when moving between system instances

Hello.

I got this unexpected behaviour. I used `guix system reconfigure ...` to

make a new system instance, used it for a while, and later booted back

into the old system. I used diferent names for the user in the first and

second system, let's call them sys1user and sys2user. I booted into the

old system and tried to login as sys1user (the user created with that

system) with it's password and this was no longer possible. root

remained untouched, so I used root to change the password and login as

usual. Done that I discovered I didn't have access to the files of

user1.

I then rebooted back into the new system, only to find the exact same

problem. in /home/sys2user all files belonged to some user called 30011.

I could of course change permissions for most of them using sudo, all

but the all-important ~/.guix-profile. Since it's a symlink to a

read-only filesystem, this was impossible.

Thanks for listening, and, sorry about the non-technical bug report.

goglosh@openmailbox.org skribis:

Yes, good point. I see how this may look confusing.

When you boot a specific generation of the system, it gets to see only

the set of users that were declared for that generation. So one sees

‘sys1user’ and ‘root’, and the other has ‘sys2user’ and ‘root’.

So when you booted the new generation, the ‘sys1user’ account was

deleted and the ‘sys2user’ account was created. When you booted again

into the old generation, ‘sys1user’ was added back and ‘sys2user’ was

deleted. This is on purpose, see http://bugs.gnu.org/19795.

Now, the problem is that passwords are state that is outside of GuixSD’s

control. Passwords are stored in /etc/shadow, and removing a user

account removes its entry in /etc/shadow. This is why you would get

uninitialized passwords when booting back in the old generation.

I think this is an acceptable “limitation” of the approach though.

Same issue: Unless the ‘user-account’ declaration asked for a specific

user ID via the ‘uid’ field (see

http://www.gnu.org/software/guix/manual/html_node/User-Accounts.html),

the UID is assigned when the account is first created.

What happens here is that maybe ‘sys2user’ got the UID 30011 at some

point, and then got a different one.

Again, I don’t thin there’s much that GuixSD can do here, because it

doesn’t control what files are created under which UID in /home, etc.

Does that make sense?

Thanks,

Ludo’.

tags 21566 notabug

close 21566 0.8.3