New kernel, simple way

The new kernel is a simple method-general Linux technology-Linux programming and kernel information. The following is a detailed description. Understand the kernel version number
Terminal, run the command: rpm-q kernel to view the kernel rpm package. For example, the returned result is:

Kernel-2.6.23.1-10.fc7

Kernel-2.6.23.1-21.fc7

This is the current two kernels on our system. If you run this command on the Early Red Hat Linux, the result may be version 2.4. In fact, linux Kernel Naming does not mean it. the kernel has a dedicated organization for management, and the kernel version naming also follows this rule. Once we are familiar with this format, we can easily identify these different kernel versions. On kernel.org, you can find all the existing kernel source code from the past to the present.

As shown above, all the versions you see are in the following format: Major version number. Revision version number. patch version number-build version number (majorversion. majorreversion. patch-build ).

The following is an explanation:
Major version: 2. Different major version numbers mean significant changes. Generally, the major version number changes mean that the entire kernel has been re-designed and will no longer be compatible with the original applications.

Revised version: 6. There are two meanings: one is that this is the sixth revision under the second main version, and the other is that if the revision version number is an even number, it indicates that this is a stable version of the kernel, if it is an odd number, it indicates that the kernel is under development.

Patch version: 23. This marks smaller kernel changes, such as Bug fixes and security enhancements. You can download a patch separately and then add it to the kernel. However, note that the main and revision versions of the patched kernel must be the same as those of the patch itself. You cannot expect a patch of version 2.4 to be applied to the kernel of version 2.6.

Build version: 1-10.fc7. This is the version number added by the Code builder. It generally only indicates the minor modifications made by the builder to the kernel.

Some Linux software, such as the firewall, are associated with certain kernel versions, which generally reach the version revision level. For example, ipchains can only run in the kernel 2.2 and later versions, while iptables is updated and can only run in the kernel 2.4 and later versions.

Upgrade the kernel
The RPM package is always the easiest installation format for RH series Linux. You can use this method to install the kernel without exception. If you download a kernel RPM package, you only need to simply execute

Rpm-I kernel. prm

Command to install the new kernel.

Note that do not use

Rpm-U kernel. rpm

Command to upgrade the kernel, the latter will make the past kernel no longer available, once you find a new kernel problems, will not be able to roll back to the previous version.

To be safe, check your grub. conf file after installing the new kernel to see if the boot item has been written for the new kernel boot.

Kernel Patch
This is a stable upgrade method. The patch is much smaller than the entire kernel, and the existing kernel can be upgraded quite smoothly.

The kernel patch source code can be easily obtained from websites such as kernel.org.

The kernel patch installation method can be found in the source code package under the commit ention/applying-patchs.txt detailed introduction.