Monday, August 29, 2011

Linux Kernel panic reboot

By default after a kernel panic Linux just waits there for a sysadmin to hit the restart or powercycle button.  This is because of the value set on "kernel.panic" parameter.

[root@linux23 ~]# cat /proc/sys/kernel/panic
[root@linux23 ~]# sysctl -a | grep kernel.panic
kernel.panic = 0
[root@linux23 ~]#

To disable this and make the Linux OS reboot after a kernel panic, we have to set an integer N greater than zero to the paramter "kernel.panic", where "N" is the number of seconds to wait before a automatic reboot.  For example , if you set N = 10 , then the system waits for 10 seconds before automatic reboot. To make this permanent, edit /etc/sysctl.conf and set it.

[root@linux23 ~]# echo "10" > /proc/sys/kernel/panic
[root@linux23 ~]# grep kernel.panic /etc/sysctl.conf
kernel.panic = 10
[root@linux23 ~]#