Running a service *just* before unmounting filesystems

[hdegoede@xxxxxxxxxx (Hans de Goede)]

Hi,

On 12-06-18 19:11, Lennart Poettering wrote:
> On Di, 12.06.18 11:33, Hans de Goede (hdegoede at redhat.com) wrote:
>> AFAIK the service actually doing the updates is supposed to call
>> systemctl reboot --force when it is done, so any targets after
>> system-update.target won't get started ?
> 
> True, the service in question could split the reboot call of course,
> if it wanted, so that you can plug things in between.

Since in this case we want to increment a boot_indeterminate counter
to indicate the last boot was not a normal boot, so no clear
success status is available I'm fine with the service doing the
increment before the updates run.

So I was thinking about adding a system-update-pre.target
and then in system-update.target add:

Wants=system-update-pre.target
After=system-update-pre.target

Would that be an acceptable solution?

I would rather not modify the existing offline-updates
services because there are 3 of them and I believe it
would be better to do this in a single place.

Regards,

Hans