Normally we press CTRL+ALT+DEL for rebooting our system, but sometimes you feel that such concurrent key press should not reboot your system. suppose your system is of production type systems which is to be prevented from such keystrokes just for security reason as someone might make some mistake and reboot the system.
For a linux systems using this shortcut you don’t need to logged in
(no user/password needed – but only console access) to reboot the system.
If you need to protect yourself from unauthorise reboot you have to disable
How to disable this shortcut :
On linux machine the action taken for CTRL-ALT-DEL is defined in /etc/inittab
on RedHat based systems the file under /etc/inittab will look like: ca::ctrlaltdel:/sbin/shutdown -t3 -r now
If we want to disable this action we only have to change this line.
We can delete it, comment it, or even replace it with something like: ca:12345:ctrlaltdel:/bin/echo “CTRL-ALT-DEL is disabled”
After making any changes to the inittab file, you will have to tell init to reload
it, in order to activate the changes. To do that, simply run as root : init q
Now try pressing CTRL-ALT-DEL you will find your system has no effect for such shortcut.