Linux/sysrq
< Linux
Emergency Reboot
echo 1 > /proc/sys/kernel/sysrq echo b > /proc/sysrq-trigger
synonymous with holding down Alt-SysRq and another key on older keyboards
Dropping 1 into /proc/sys/kernel/sysrq tells the kernel that you want to enable SysRq access (it’s usually disabled).
The second command is equivalent to pressing Alt-SysRq-b on a QWERTY keyboard.
If you want to keep SysRq enabled all the time, you can do that with an entry in your server’s sysctl.conf:
kernel.sysrq = 1
Ref: Linux: emergency reboot or shutdown with magic commands - major.io - https://major.io/2009/01/29/linux-emergency-reboot-or-shutdown-with-magic-commands/
Emergency Shutdown
echo 1 > /proc/sys/kernel/sysrq echo o > /proc/sysrq-trigger