[systemd-devel] Antw: [EXT] Re: Run "ipmitool power cycle" after lib/systemd/system-shutdown scripts

[Ulrich Windl]

>>> Lennart Poettering <lennart at poettering.net> schrieb am 10.02.2022 um 11:31
in
Nachricht <YgTpdVFRgL+uQoY9 at gardel-login>:
> On Mi, 09.02.22 22:05, Etienne Champetier (champetier.etienne at gmail.com) 
> wrote:
> 
>> Hello systemd hackers,
>>
>> After flashing the firmware of some pcie card I need to power cycle
>> the server to finish the flashing process.
>> For now I have a simple script in lib/systemd/system-shutdown/ running
>> "ipmitool power cycle" but I would like to make sure it runs after
>> other scripts like fwupd.shutdown or mdadm.shutdown
>>
>> Is there any way to have systemd cleanly power cycle my server instead
>> of rebooting it ?
> 
> What does "power cycle" entail that "reboot" doesnt? i.e. why doesn't
> "systemctl reboot" suffice?

My guess is that some smart cards with their own foirmware and CPu do not
reboot unless they are power cycled, so maybe if the firmware upgrade on the
card does not force it to reboot, it my need a power cycle.

> 
> /usr/lib/systemd/system-shutdown/ drop-ins are executed before the OS
> transitions back into the initrd — the initrd will then detach the
> root fs (i.e. undo what it attached at boot) and actually reboot. This
> means if your command turns off the power source you should stick it
> in the initrd's shutdown logic, and not into
> /usr/lib/systemd/system-shutdown/. If you are using RHEL this means
> into dracut. But adding it there is something to better discuss with
> the dracut community than here.

My guess is that it would be handled best by some special GRUB boot menu entry
(like "boot 'power cycle' once).

Regards,
Ulrich

> 
> Lennart
> 
> --
> Lennart Poettering, Berlin