After retrieving all of the necessary packages, it is time to upgrade the existing kernel.

At a shell prompt, change to the directory that contains the kernel RPM packages. Use -i argument with the rpm command to keep the old kernel. Do not use the -U option, since it overwrites the currently installed kernel, which creates boot loader problems. For example:

~]# rpm -ivh kernel-<kernel_version>.<arch>.rpm 

The next step is to verify that the initial RAM disk image has been created. Refer to Section 23.5, “Verifying the Initial RAM Disk Image” for details.