Chapter 30. Manually Upgrading the Kernel

The Red Hat Enterprise Linux kernel is custom-built by the Red Hat Enterprise Linux kernel team to ensure its integrity and compatibility with supported hardware. Before Red Hat releases a kernel, it must first pass a rigorous set of quality assurance tests.
Red Hat Enterprise Linux kernels are packaged in the RPM format so that they are easy to upgrade and verify using the Yum or PackageKit package managers. PackageKit automatically queries the Red Hat Network servers and informs you of packages with available updates, including kernel packages.
This chapter is therefore only useful for users who need to manually update a kernel package using the rpm command instead of yum.

Warning

Whenever possible, use either the Yum or PackageKit package manager to install a new kernel because they always install a new kernel instead of replacing the current one, which could potentially leave your system unable to boot.

Warning

Building a custom kernel is not supported by the Red Hat Global Services Support team, and therefore is not explored in this manual.
For more information on installing kernel packages with Yum, see Section 8.1.2, “Updating Packages”. For information on Red Hat Network, see Chapter 6, Registering the System and Managing Subscriptions.

30.1. Overview of Kernel Packages

Red Hat Enterprise Linux contains the following kernel packages:
  • kernel — Contains the kernel for single, multicore and multiprocessor systems.
  • kernel-debug — Contains a kernel with numerous debugging options enabled for kernel diagnosis, at the expense of reduced performance.
  • kernel-devel — Contains the kernel headers and makefiles sufficient to build modules against the kernel package.
  • kernel-debug-devel — Contains the development version of the kernel with numerous debugging options enabled for kernel diagnosis, at the expense of reduced performance.
  • kernel-doc — Documentation files from the kernel source. Various portions of the Linux kernel and the device drivers shipped with it are documented in these files. Installation of this package provides a reference to the options that can be passed to Linux kernel modules at load time.
    By default, these files are placed in the /usr/share/doc/kernel-doc-<kernel_version>/ directory.
  • kernel-headers — Includes the C header files that specify the interface between the Linux kernel and user-space libraries and programs. The header files define structures and constants that are needed for building most standard programs.
  • kernel-firmware — Contains all of the firmware files that are required by various devices to operate.
  • perf — This package contains supporting scripts and documentation for the perf tool shipped in each kernel image subpackage.