What is the difference between the two? In a Linux 2.6.x kernel.
If you are kernel development you could have sudden kernel panic, SysRq key will be very valuable. The magic SysRq key is a key combination in the Linux kernel which allows the user to perform various low level commands regardless of the system’s state.
normally when you do
Alt+SysRQ+b system reboots without
umounting or sync
This command is often used to recover from freezes, or to reboot a computer without affecting the current file system.
SysRq is much similar to attempting reset button physically on server.
No daemons will be shut down gracefully, no filesystem sync will occur, but you may get the wrath of a fsck (or worse, a non-booting server) upon reboot.