Option to restart/start a service using sysrq magic key

[lennart@xxxxxxxxxxxxxx (Lennart Poettering)]

On Mo, 11.06.18 18:13, P.R.Dinesh (pr.dinesh at gmail.com) wrote:

> Is it possible to restart/start a service using sysrq magic key.

That's a kernel concept, systemd is userspace software. Thus we can't
really hook into sysrq handling. Sory.

> In my setup we have a getty service which controls the console.  For
> some

The getty unit files we ship generally include Restart= lines to
ensure they get restarted quickly.

> reason this gets stopped.  Once the getty service is stopped the console
> connection to the device is hung.  The only way to recover is to reboot the
> device.  In such case can we use any sysrq magickey to start or restart a
> service or switch to a emergency target?

The kernel allows you to map Ctrl-Alt-Up to some special operation,
and systemd allows that too, as it exposes that event as a request to
pull in kbrequest.target. Fill that with anything you like.

Lennart

-- 
Lennart Poettering, Red Hat