Systemd: how to get into rescue mode

[Little Girl]

Hey there,

Tom H wrote:

>"procps" ships "/etc/sysctl.d/10-magic-sysrq.conf" which sets
>"kernel.sysrq = 176" and this setting prevents using "e" and "i"
>among others.

>What's "cat /proc/sys/kernel/sysrq" on your system? If it's not "176"
>either you or MATE (?) are overriding it.

It returns 176 on my system.

A bit of research on "kernel.sysrq = 176" turned up that the
Alt+SysRq+REISUB and Alt+SysRq+REISUO key combinations no longer take
control of the keyboard away from the X server, no longer send the
SIGTERM signal to all processes, and no longer send the SIGKILL
signal to all processes. They do, however, still sync all mounted
filesystems, remount all mounted filesystems in read-only mode, and
shut off the system or reboot it without unmounting or syncing
filesystems.

When I did those key combinations, apparently the REI key presses
were simply ignored and the SUB and SUO key presses were obeyed. Now
the question becomes whether we should just be using the SUB or SUO
key combinations in emergencies or whether there's a new and improved
way of handling such situations. If you were dealing with a frozen
system (which wasn't the case with the OP in this thread), I suppose
Systemd commands would be useless, since you probably wouldn't be
able to issue them.

-- 
Little Girl

There is no spoon.