Bug#976101: systemd: Offline update installation in systemd (via gnome-update) doesn't cleanly unmount filesystem

[Michael Biebl]

Am 06.12.20 um 17:04 schrieb Josh Jones:
> It is the root filesystem which is failing to be remounted read-only -
> this is a simple setup with only one filesystem for the whole system.
> 
> It seems to be happening right at the very very end of the shutdown
> sequence - I have attached a picture of the error; quality is poor
> because I had to capture it from video footage. Is there any way to
> even have anything saved to disk so late in the sequence?

With the shutdown hook described in README.Debian and 
https://freedesktop.org/wiki/Software/systemd/Debugging/#index2h1
(install the hook as /lib/systemd/system-shutdown/debug.sh without the 
/usr prefix) you can gather logs right until the end

> Thanks for your help and attention with this; I'm willing to try
> whatever you suggest to help work out what's going on - if that is even
> possible..!


>> You might also have a look at
>> https://salsa.debian.org/systemd-team/systemd/-/blob/debian/master/debian/README.Debian
>>
>> "Debugging boot/shutdown problems"
>> to gather logs after journald has been shut down.