On x86 - You press the key combo 'ALT-SysRq-<command key>'. Note - Some keyboards may not have a key labeled 'SysRq'. The 'SysRq' key is also known as the 'Print Screen' key.
* What are the 'command' keys? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 'r' - Turns off keyboard raw mode and sets it to XLATE.
'k' - Secure Access Key (SAK) Kills all programs on the current virtual console. NOTE: See important comments below in SAK section.
'b' - Will immediately reboot the system without syncing or unmounting your disks.
'o' - Will shut your system off (if configured and supported).
's' - Will attempt to sync all mounted filesystems.
'u' - Will attempt to remount all mounted filesystems read-only.
'p' - Will dump the current registers and flags to your console.
't' - Will dump a list of current tasks and their information to your console.
'm' - Will dump current memory info to your console.
'0'-'9' - Sets the console log level, controlling which kernel messages will be printed to your console. ('0', for example would make it so that only emergency messages like PANICs or OOPSes would make it to your console.)
'e' - Send a SIGTERM to all processes, except for init.
'i' - Send a SIGKILL to all processes, except for init.
'l' - Send a SIGKILL to all processes, INCLUDING init. (Your system will be non-functional after this.)
'h' - Will display help ( actually any other key than those listed above will display help. but 'h' is easy to remember :-)
On Mon, Nov 05, 2001 at 09:10:56AM +0000, Jenny_Hopkins@toby-churchill.com wrote:
This lovely message was waiting to greet me on all consoles of my debian box when i came in to work this morning, and I can't telnet in. A search on google says:
Upgrade to 2.2.19 , that should fix the problem. It's a bug in the releases between 2.2.14 and 2.2.19, afaik.
Has anyone heard of this before? I'm using kernel 2.2.18pre 21, activity on box over weekend should have been minimal apart from backups running. And what were those keys that try to reboot cleanly again? (not the ctl-alt-del) (Hope it isn't going to be one of "those" days....) Nice to meet so many folk yesterday. Jenny.