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

[Karl Auer]

On Fri, 2022-01-21 at 23:27 +0100, Bo Berglund wrote:
> SSH server seems to disconnect the SSH client session when the user
> logs off the desktop!
> [...]
> The disconnect does not happen directly when I log off from the
> desktop but after some time (a couple of minutes)

So it's NOT "when the user logs off". Is it really a "couple of
minutes"? Sessions drop normally after less than a minute if it's
keepalives.

Not counting human intervention, ssh sessions generally drop because:

- the network connection fails
- one or the other end changes IP addresses
- one or the other end boots, sleeps or turns off

Keepalives are  bit misnamed - they are not really there to keep the
connection up, they are there to detect when the connection drops. Not
having them configured should not cause a failure, though sometimes
various devices will drop a long-silent connection (e.g., NAT devices
unmapping a session).

>  the SSH session (via PuTTY) just disconnects mid way in a file edit
> or other activity! At the same time I hear from the box how the data
> drive is powered off and the heads parked.

That sounds a bit as if the remote is going to sleep.

> After this it is not possible to connect by SSH anymore

That still sounds as if the remote has gone to sleep.

Even if you don't think that is the case, I suggest you *prove* it is
not the case before investigating more esoteric explanations.

Regards, K.

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

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