Unable to login after upgrade

[Liam Proven]

On Sat, 31 Oct 2020 at 15:23, Gregory Gamble <greg.gamble at uwa.edu.au> wrote:
>
> Indeed. Thanks. Apologies for the delay in reply.
> I had a few minutes to try Chris's suggestion of the text console login
> this morning, before being otherwise engaged most of the day,
> and yes, I was able to login at the desktop via Ctrl+Alt+F2.

Thought so.

> I tried typing X which crashed.

`X` alone won't work. It can vary, but normally the command is:

startx

Note that capitals are important -- so StartX or startX won't work.

> So as diagnosed, the desktop crashing is the problem.

This alone isn't conclusive but I am confident this is the issue. It's
not uncommon on Linux, sadly. It's not an Ubuntu problem.

Things you can try:

* On the login screen there is usually a little control somewhere -- a
cogwheel or something -- that lets you change the desktop you're
logging into. So for instance if you're using GNOME 3 (the Ubuntu
default for the last 2 versions) then it's probably got something
like:

Ubuntu on Wayland
Ubuntu on X.org
GNOME on Wayland
GNOME on X.org

Try all the other ones. You may find one will work.

The problem could lie in the settings of your particular account. If
there are other accounts, try them. If there are no other accounts, is
there a "guest" option? Try that.

If anyone else can log in, X is OK and the problem lies in your
personal profile.


> I had looked at Volker's suggestion of looking at the log file for gdm3
> prior to this, but like Volker /var/log/gdm3 for me is empty.

I think that only tells you if the login screen crashed.

>
> I didn't do the above from the console, but I just did the above
> via a remote login, and instead of:
>
> apt full-upgrade -y
>
> which failed with:
>
> E: Invalid operation full-ugrade

Sounds like a typo.

Looks like you missed the P.

> I did:
>
> apt upgrade -f -y
>
> which I presume is the same.

Nope.

The "old" form of the command is:

apt-get dist-upgrade -y

> I'm not sure that a full disk was the problem, but after the above,
> here is what df gives (I 'sanitised' a couple of lines):
>
> root@<machine>:<home-dir># df

Try `df -h` for human units (MB and GB).

> Filesystem                         1K-blocks      Used Available Use% Mounted on
> /dev/sda1                          479668904  20867708 434365588   5% /

5% used is not a problem!

> Fatal server error:
> [  5001.450] (EE) parse_vt_settings: Cannot open /dev/tty0 (Permission denied)

> Is there anything helpful there?

X troubleshooting is complex, and I'm not the world's greatest expert,
but the line above looks suspicious.

> Thanks everyone for your help.
> I guess I should have know about the console login idea.
> This was such a great hint.

Glad it helped!

I suspect you have a GNOME extension or something that is crashing,
but I am not sure.

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