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

[Karl Auer]

On Sun, 2022-01-23 at 11:26 +0000, Colin Law wrote:
> As I said, something very odd is going on.  The syslog just stops
> without a normal shutdown so something reset the processor.

Very odd! Such a precise interval suggests control OR a software
process that finishes with a reboot like a watchdog, OR a natural
process that takes a very similar time to cause a reboot.

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.

The mystery for me is why logging in to the desktop stops the reboots!

What does "last | head" show?

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.

Regards, K.

-- 
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Karl Auer (kauer at biplane.com.au)
http://www.biplane.com.au/kauer

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