Raising Elephants Is So Utterly Boring

Taken from http://en.wikipedia.org/wiki/Magic_SysRq_key
"Raising Elephants Is So Utterly Boring" is a mnemonic device for remembering a keystroke sequence that should be used as an alternative to hitting the power button if a Linux system should ever freeze and need to be rebooted.
Alt + SysRq + R – takes the keyboard out of raw mode.
Alt + SysRq + E – terminates all processes (except init).
Alt + SysRq + I – kills all processes (except init).
Alt + SysRq + S – synchronizes the disk.
Alt + SysRq + U – remounts all filesystems read-only.
Alt + SysRq + B – reboots the machine.
Or it can be remembered as "BUSIER" in reverse.
"Raising Skinny Elephants Is Utterly Boring" is an alternative mnemonic for the same series of keystrokes, though changing the position of the disk synchronization to before terminating and killing all processes.
Regardless of which of the above hotkey sequences are chosen, they should be entered in slow succession, giving the system a chance to complete earlier steps before moving on to subsequent ones. Typing the sequence slowly may allow the system to safely terminate most or all processes before the more drastic kill command is invoked. Also, to minimize the chance of data corruption, it is a good idea to wait between the disk synchronization command and the unmount and finally the reboot command.
An alternative to issuing the REISUB/RSEIUB keystrokes is to just press Alt + SysRq + R, followed by Ctrl + Alt + Del. This is the equivalent of issuing a shutdown now command at a root console; it does take a short while for the system to shut down after the Ctrl + Alt + Del keystroke. However, not all Linux systems support this easier method.


Special thanks to my sister :)

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