2008/12/21 Archives

21-12-2008 12:33

Magic Tricks To Get Out of Trouble With the Sysreq Key

A list of magic SysReq keys for the Linux Kernel. Link here.

Press Alt-Sysreq, then one of the following letters:

r Unraw: Restores the keyboard after an X crash or similar.
0 Changes console loglevel to 0 and so reduces error messages.
k System attention key: Kills all processes on the current virtual console.
e Terminate: Kills all processes except init on the current terminal.
i Kill: Kills all processes except init, everywhere.
s Sync: Attempts to sync all mounted filesystems. Outputs OK and Done when it's managed. This can reduce the chances of needing to run fsck at a later stage so it can be useful if you're having disk problems.
u Umount: Attempts to remount all mounted filesystems read-only.
b Reboot: immediately reboots the system without syncing or unmounting disks. Not a good idea unless in extremis! This may lead to data loss.
p Dumps current registers and flags to the console.
m Dumps current memory info to the console.

Posted by DaveQB | Permanent Link | Categories: IT