Ubuntu 20.04.3 desktop (Cinnamon) - SSH disconnects when user logs off the desktop!

[Bo Berglund]

On Mon, 24 Jan 2022 08:22:19 +1100, Karl Auer <kauer at biplane.com.au> wrote:

>I often set up a cron job that reboots to clear iptables; if I lock
>myself out, a reboot will save me in five minutes. There are watchdogs
>out there that look for failures and reboot. And a natural process
>could be something like overheating. Just examples, I'm not suggesting
>any of these are actually the case.

My reporter is a cron job (user crontab -e)
With this line:

@reboot /home/bosse/bin/ipreport.sh 60 > /dev/null 2>&1

>The mystery for me is why logging in to the desktop stops the reboots!
>
>What does "last | head" show?

Cannot say, see below...

>
>Also try disconnecting everything you can from the system - keyboard,
>mouse, network, monitors, USB hubs, headphones/speakers/microphones,
>external drives etc - and see if these reboots keep happening.
The only connections are:
- Power adapter
- LAN cable
- DisplayPort monitor cable
- The Logitech keyboard USB receiver

What I did in the afternoon was to use the remaining space on the drive to
install ubuntu-mate-20.04.3-desktop-amd64 in order to check if that would be
better.
It turns out that it too reboots the same way only with a longer period of a bit
over 10 minutes. And this happens also when the desktop is logged into.

So then I used GParted to create a bit more space in order to install Ubuntu
Server 20, basically giving up on the GUI part since that is not how the
computer will be used normally.

However, it seems like the server installer is not as clever as the Ubuntu
Desktop installers so it trashed the drive! Cannot find operating system!
The efi partition was not created as the desktop installers did..

So I no longer have access to the two Ubuntus I installed previously.
Their partitions were both gone.

So tonight I made a final attempt at installing linuxmint-20.3-cinnamon-64bit
and it too is rebooting, in this case 11 minutes after I logged out from the
desktop to the login screen... :(

I have now reached the next reboot yet so I can time the cycle: 673 s this time.
I will let it run like this for an hour or so and then inspect the log the
reporter creates to get a handle on the repeatability.

Can I modify the startup somehow to make it automatically log me in to the
desktop when it boots? Then it would never stay on the login screen and the
reboots might not happen...
It is available during install, but can it be done later too?


-- 
Bo Berglund
Developer in Sweden