So you try to update you server and it says that you /boot pertision is full and cant update kernel.
Will this is how you remove some old kernels so you can keep your system up to date.
1. First what kernel is running now (We dont want to remove that kernel)
uname -a Linux install 2.6.32-279.19.1.el6.x86_64 #1 SMP Tue Nov 6 23:43:09 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux
Ok kernel 2.6.32-279.14.1 is running now
What kernels are install
rpm -q kernel kernel-2.6.32-279.el6.x86_64 kernel-2.6.32-279.14.1.el6.x86_64 kernel-2.6.32-279.19.1.el6.x86_64
So then remove the kernels that ARE NOT RUNNING ON
rpm -e kernel-2.6.32-279.el6.x86_64
And now you can install the new kernel