Before upgrading the kernel, take a few precautionary steps. If the system has a diskette drive, the first step is to make sure a working boot diskette exists for the system in case a problem occurs. If the boot loader is not configured properly to boot the new kernel, the system cannot be booted into Red Hat Enterprise Linux without a working boot diskette.
To create the boot diskette, login as root, and type the following command at a shell prompt:
/sbin/mkbootdisk `uname -r`
Refer to the man page for mkbootdisk for more options.
Reboot the machine with the boot diskette and verify that it works before continuing.
Hopefully, the diskette will not be needed, but store it in a safe place just in case.
To determine which kernel packages are installed, execute the following command at a shell prompt:
rpm -qa | grep kernel
The output contains some or all of the following packages, depending on the system's architecture (the version numbers and packages may differ):
kernel-2.4.21-1.1931.2.399.ent kernel-source-2.4.21-1.1931.2.399.ent kernel-utils-2.4.21-1.1931.2.399.ent kernel-pcmcia-cs-3.1.31-13 kernel-smp-2.4.21-1.1931.2.399.ent
From the output, determine which packages need to be download for the kernel upgrade. For a single processor system, the only required package is the kernel package. Refer to Section 39.1 Overview of Kernel Packages for descriptions of the different packages.
In the filename, each kernel package contains the architecture for which the package was built. The format is kernel-<variant>-<version>.<arch>.rpm, where <variant> is smp, utils, etc. The <arch> is one of the following:
x86_64 for AMD64 and Intel® Extended Memory 64 Technology (Intel® EM64T).
ia64 for the Intel® Itanium™ architecture.
ppc64pseries for the IBM® eServer™ pSeries™ architecture.
ppc64iseries for the IBM® eServer™ iSeries™ architecture.
s390 for the IBM® S/390® architecture.
s390x for the IBM® eServer™ zSeries® architecture.
x86 variant: The x86 kernels are optimized for different x86 versions. The options are as follows:
athlon for AMD Athlon® and AMD Duron® systems
i686 for Intel® Pentium® II, Intel® Pentium® III, and Intel® Pentium® 4 systems