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Reboot machine when everything is hanging

Terminal - Reboot machine when everything is hanging
<alt> + <print screen/sys rq> + <R> - <S> - <E> - <I> - <U> - <B>
2009-02-20 07:28:56
User: dizzgo
89
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Reboot machine when everything is hanging

If the machine is hanging and the only help would be the power button, this key-combination will help to reboot your machine (more or less) gracefully.

R - gives back control of the keyboard

S - issues a sync

E - sends all processes but init the term singal

I - sends all processes but init the kill signal

U - mounts all filesystem ro to prevent a fsck at reboot

B - reboots the system

Save your file before trying this out, this will reboot your machine without warning!

http://en.wikipedia.org/wiki/Magic_SysRq_key

Add to favourites | Report as malicious

Alternatives

There is 1 alternative - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

doesn't work on fedora ;=s

Comment by renich 220 weeks and 2 days ago

This works! (but here's hoping you don't have to use it. :-)

Comment by mpb 220 weeks and 2 days ago

I think it depends on they keyboard: I haven't had much luck with USB ones.

Although debatable, it should also be REISUB. A program could write data when sent the term signal (as that's a clean shutdown command), and not be synced (which is done first), causing the data to lounge around in cache and then vanish.

Also, it's worth noting that you should wait a second or two between the U and B, just to make sure that everything has in fact been written to disk.

Comment by clockworkavian 219 weeks and 6 days ago

mnemonic for REISUB key combination is ; it is reverse of BUSIER

Comment by alperyilmaz 216 weeks ago

Well.......

This trick will work if and only if you have set some kernel parameter.

Interested guys can find out the parameters and post it here.

Long days before, I was playing with this and not do not remember the parameters but they are most probably in the "kernel hacking" section ( 2.6.21 )

Good Luck....

Comment by Satish 192 weeks ago

Your kernel needs CONFIG_MAGIC_SYSRQ=y

Comment by hfs 188 weeks ago

I pressed

<alt> + <print screen> + <r>

and my computer went into an infinite loop of opening the print screen dialog. WTF?

Comment by csmeder 176 weeks and 2 days ago

it worked for me after i launched otherwise when doing prntscrn i get screenshot window. it not useful when freezing since unless you are in the tty. ubuntu 10.4

Comment by firstohit 149 weeks and 1 day ago

Lovely! I keep a printed version of the Wikipedia article in my desks drawer.

Comment by jabz 123 weeks ago

Your point of view

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