reisub not working anymore

Lucien_Lachance

used to work but doesent anymore
the command i used: sudo echo 'kernel.sysrq=1' | sudo tee /usr/lib64/sysctl.d/99-reisub.conf
ive got a 75% keyboard to ive always used printscr (fn+p) instead of SysRq and it has always worked until a few months ago
has something changed so a different command is needed?

for reference: https://blog.kember.net/posts/2008-04-reisub-the-gentle-linux-restart/

AlphaElwedritsch

Lucien_Lachance and it has always worked until a few months ago

I wonder how often have you used it, or do you need it?
I cannot remember that I ever could need it. At least not on Solus 😉

brent

along with my fwupd error at devtracker, that makes three recent threads where tried and true terminal commands stopped working. the mind is good at seeing patterns, and none of the error outputs have anything to do with each other but it is a strange coincidence---

--if you want me to replicate, what will happen if I run it?

Lucien_Lachance

brent if you run reisub your computer should reboot, its for when the computer is hard crashed and ctrl-alt-del doesent work(a safer alternativeto holding in the power button)

the command i pasted just enables reisub, and it wont work until after a reboot.
then you press alt and keep it pressed all the time.
while alt is pressed, press the following in this order: SysRq/printscr, r,e,i,s,u,b
rougly 1 sec between each

it should just reboot the computer even if its hard locked

brent

Lucien_Lachance

no sysreq but did have print screen

ran command
output said kernel entry created or something
rebooted
did this twice
one with alt pressed whole reboot
the other with alt pressed after system completely up
then printscr, r, e, i, s, u, b, one second in between

result: nothing happened
no reboot, no lockout, etc

Lucien_Lachance

brent thanks for confirming

as i said it used to work, would like to have it back as its very handy when disaster strikes

brent

it's probably a DE-agnostic error but for the record I used Budgie to replicate. think you do too

Lucien_Lachance

brent gnome atm, but it doesent work on plasma either

Solarmass

I haven't used it in years.
I wonder why do you put config in /usr/lib64/sysctl.d/99-reisub.conf
I have it in /etc/sysctl.d/

https://linuxconfig.org/how-to-enable-all-sysrq-functions-on-linux

Lucien_Lachance

Solarmass i dunno, cos my howto says so, and cos /etc/sysctl.d/ doesent exist on my system i suppose

Harvey weird, could it be because i have to use fn+p, it did however work before

Harvey

Seems to work for me. I will point out tho that you do not need sudo for the echo.

The reason we pipe it to sudo tee is because sudo echo "test" > /path/to/file will only apply sudo to before the operator ( > ) and thus does not gain elevated privileges to write to a restricted path.

brent

https://forum.endeavouros.com/t/desktop-is-freezing-and-i-cannot-pinpoint-the-issue/74664

about Gnome and hard reboots (from freezes) but detours into "REISUB key combination " and its role in all this.
posted as food for thought

Solarmass

Lucien_Lachance i dunno, cos my howto says so, and cos /etc/sysctl.d/ doesent exist on my system i suppose

in many cases you have to create it yourself in /etc and copy config examples form /usr/share/...
I think it's a proper way 🙂

Lucien_Lachance

hmm i solved it. fn+p(printscr) doesent work anymore but checking my keyboards manual and looking up what the US keyboard layout looks like it turns out that fn+the button to the left of the right shift (- on NO layout) also functions as printscr, and with it reisub works!

Lucien_Lachance

AlphaElwedritsch i struggled with a hardware related freezing for a few months, resulting in complete freezes. reisub was very handy then (turned out it was related to unvervolting)