Are both Linux kernel versions and distribution versions free?
Linux is a free operating system no matter which version it is. Red Hat Linux and the like charge a fee, not for the Linux operating system, but for the services and solutions it provides. There are no patents or copyrights in the Linux operating system, but the Red Hat logo in Red Hat Linux, such as the logo, has trademark rights and cannot be used indiscriminately
What are the rules for Linux kernel version numbers?
There are two types of Linux kernel versions: stable version and development version. The Linux kernel version number consists of 3 numbers: r.x.y
r: The currently released main version of the kernel.
x: Even numbers represent stable versions; odd numbers represent versions under development.
y: The number of bug fixes.
What do each bit of the kernel version number represent?
Take the version number as an example: 2.6.9-5.ELsmp,
r:2, major version No.
x: 6, minor version number, indicating stable version
y: 9, revision number, indicating the number of modifications
The sum of the first two numbers Together the core series can be described. For example, the stable version 2.6.0 is the 2.6 version of the kernel series.
5: Indicates the fifth fine-tuning patch of this current version, and ELsmp points out that the current kernel is specially tuned for ELsmp
EL: EnterpriseLinux; smp: Indicates support for multi-processing processor, indicating that the kernel version supports multi-processors
Knowledge extension
There are generally three types
1smp
2bigmem
3 General kernel
When RedHatLinux is booted, the GRUB boot menu will have two options, namely
RedHatEnterpriseLinuxES (version number.ELsmp)
< p>RedHatEnterpriseLinuxES-up (version number.EL)What do these two mean?
In fact, this is the GRUB boot when the system is turned on - single processor and Differences in symmetric multiprocessor startup core files.
RedHatEnterpriseLinuxES(version number.ELsmp)multipleprocessor(symmetricmultiprocessing)
RedHatEnterpriseLinuxES-up(version number.EL)uniprocessor
The following is the SUSE and RedHat startup menu List the selectable options in
SUSE
Version number-default:SUSELinuxkernelforuniprocessormachinesDefault option, support single-processor machines
Version number-smp:SUSELinuxkernelthatsupportssymmetricmultiprocessingandupto4GBofRAM
Symmetric multiprocessing machine that supports 4GB memory
Version number-bigsmp:SUSELinuxkernelsupportssymmetricmultiprocessingandupto64GB
Symmetric multiprocessing machine that supports 64GB memory
< p>RedHatLinuxVersion number.EL:RedHatLinuxkernelforuniprocessormachines supports single-processor machines
Version number.ELhugemem:RedHatLinuxkernelthatsupportsupto64GBofRAM
Supports symmetrical multi-processor machines with 64GB of memory
Version number.ELsmp:RedHatLinuxkernelthatsupportssymmetricmultiprocessingsymmetric multiprocessor machine, supports 4G memory
In some cases you need to support features 1 and 2, then you can: Recompile the kernel, Just select the options corresponding to your configuration on the processor and memory options.
How to download the source code of the corresponding kernel version?
Under normal circumstances, you can download it directly from the official website: http://www.kernel.org.
The disadvantage is that any distribution version that has been specially optimized and adjusted for any kernel is Inappropriate, especially fedoraubuntu. After all, they have put a lot of patches in the kernel and made a lot of optimizations. If you use the official source code directly, you will not be able to enjoy these things. The newer the kernel, the better. The more suitable, the better
So it is best to go to the publisher's official website to download, because the official has provided compiled source code rpm packages.
How to use the corresponding kernel source package?
Take the kernel source code officially provided by fedora: kernel-2.6.23.9-85.fc8.src.rpm as an example
First, install the source code
#rpm -ivhkernel-2.6.23.9-85.fc8.src.rpm
Then, convert the source code
Before converting, please ensure that there is a redhat directory in the /usr/src/ directory (generally/ usr/src/ is an empty directory).
#rpmbuild-bp--target=$(uname-m)/usr/src/redhat/SPECS/kernel.spec
This will place the source code in /usr/src /redhat/BUILD/kernel-2.6.23/.
There are two useful folders here: .
linux-2.6.23.ARCH - This is the package provided by kernel.org after Fedora patches and upgrades. That is, the patched kernel 2.6.23.9-85.fc8
The output of ARCH is consistent with uname-m, usually i686.
If you want different output, you can specify it using the "--target=" option.
vanilla - This is the standard source code provided by kernel.org that has not been patched or upgraded.
What is the Linux kernel and what does it do?
The Linux kernel is an operating system (OS) kernel, essentially defined as Unix-like. It is used in different operating systems, mainly in the form of different Linux distributions.
The Linux kernel is the bottom layer of the entire operating system. It is responsible for driving the entire hardware and providing core functions required by various systems, including firewall mechanisms, whether to support file systems such as LVM or Quota, etc. If the kernel doesn't recognize a piece of the latest hardware, then the hardware can't be driven, and you can't use the hardware.
What is the difference between linux version and kernel version?
First understand a concept.
The entire actual Linux system is composed of three parts: kernel, software, and tools.
The kernel was developed and tested by an early team of hacker engineers. Later, many engineers who advocated open source joined in to develop software applications. Linux gradually improved and its functions became increasingly complete and powerful. When the popularity became more widespread, Many commercial companies add their own system tools to the kernel and software so that users who do not know computers can use the Linux system, and then package it into a complete system installation program for users to install and use.
This way The packaged Linux is called a release version of Linux, and the corresponding Linux kernel version refers to the kernel part developed and maintained by kernel development engineers.