apt full-upgrade causes system lock-up

[Bo Berglund]

I don't know if this belongs here but I'll make a test:

I have an HP ProDesk system on a remote location with Linux Mint 20.3.
I access it via PuTTY (SSH) mostly but I also have a possibility to use VNC
towards it, but that happens very seldom.
The remote and home networks are connected via VPN on the router.

Today I experienced a weird lock-up when doing a sudo apt full-upgrade
operation.

After it ran for a while it stalled for a long time with something that sat at
the 90% position.
Then it finally finished with an error message as follows:

....
(apt output messages streaming by)
Get:19 http://packages.linuxmint.com una/upstream amd64 firefox-locale-en amd64
101.0+linuxmint1+una [691 kB]
Fetched 86,7 MB in 15s (5 854 kB/s)
Preconfiguring packages ...

Here is where it sat for a long time at 90+% until that disappeared and the
following was printed:

dpkg: unrecoverable fatal error, aborting:
 loading files list file for package 'linux-headers-5.4.0-105': cannot read
/var/lib/dpkg/info/linux-headers-5.4.0-105.list (Input/output error)
Bus error
E: Sub-process /usr/bin/dpkg returned an error code (2)
W: Problem unlinking the file /var/cache/apt/pkgcache.bin - pkgDPkgPM::Go (30:
Read-only file system)

At this point it became unresponsive.

I tried another PuTTY session and got to the user and password entry step but
then it got unresponsive again.

Since this sits about 100 km away I have put a remotely controllable power
switch in the feed to the system so by cycling power to the now locked up system
it came back up.

The reason I have the remote power switch installed is because a few months back
I had a similar situation also after an apt upgrade, but at that time it did not
even accept SSH calls, but responded to ping.
And a month or so ago I had to use it in order to get the system back on-line.

Is this a known Mint issue or is it a glitch?
But the glitch seems to happen now and then even now.


-- 
Bo Berglund
Developer in Sweden