Date: 2008sep27 OS: Linux Q. I know I need to reboot my box when the kernel is updated for it to come into effect but I have automatic update running so... I can I tell if I need to reboot my machine? A. Compare the currently running kernel version with those installed. To see what's currently running do:

uname -r

And you might get:

2.6.25.9-76.fc9.i686

To see what's installed (on RedHat/Fedora/CentOS) do:

rpm -q kernel

And you might get:

kernel-2.6.25.6-55.fc9.i686 kernel-2.6.25.9-76.fc9.i686

If the version you are running is the biggest one installed then you don't need to reboot.