RHEL6 really should not be using lilo unless it is dual booting with an already installed Debian install
redhat/cent/SL/fedora and even SUSE are Grub based
rhel6 is using the older legacy grub 0.9 as default
there are NO steps to take
you run a update and yum auto adds a new boot line if needed
this is the ONLY needed step
Code:
su -
yum update
---- then IF a kernel is updated then -------
reboot