# AAAAAAlok How to Check Kernel Version in Linux?

## AAAAAAHow to Check Kernel Version in Linux?
The Linux kernel version refers to a specific release of the Linux kernel software. The kernel is the core component of the Linux operating system, serving as a bridge between the hardware and software layers. It provides essential services and functionality to the operating system and the applications that run on it. In Linux, there are multiple kernel versions available, and there may be situations where you need to check the version of the installed Linux kernel on your system. This can be particularly useful when troubleshooting hardware issues or for general system maintenance.
The **versioning technique** used by the Linux kernel consists of three digits separated by periods, often in the form "x.y.z". Here is a description of each element:

**Major Version (x)**: The Linux kernel's major version represents significant updates and changes to the kernel. It denotes significant architectural changes, introduces new features, and brings significant performance and functionality improvements. In some cases, upgrading to a new major version may necessitate compatibility changes. To summarise, a major version represents significant updates and improvements to the Linux kernel.

**Minor Version (y):** The Linux kernel's minor version represents smaller updates, bug fixes, and feature enhancements within a given major version. These updates usually include new hardware support, security patches, and performance improvements. Minor version updates are designed to be backward compatible, which means they can be applied to the same major version without causing problems.

**Patch Level (z):** The patch level of the Linux kernel denotes incremental updates and bug fixes for a specific minor version. Patch updates are primarily concerned with addressing software bugs, addressing security flaws, and improving overall stability. These updates are backward compatible, which means they can be applied to the same major and minor versions without causing compatibility issues.
To check the Linux kernel version you can use the following method.
### Using uname Command

The uname command in Linux is used to gather information about the system and its kernel. It stands for "Unix Name" and offers several options to display different types of information.

uname -r

image 1

In the above example, the kernel version 5.15.0-73 represents

5- Kernel version

15-Major revision

0-Minor revision

73-Patch number

generic - Distribution-specific details.

Alternatively, if you want more detailed information about the kernel, you can use the following command:

uname -a

This will display additional information such as the kernel version, release date, system architecture, and more.

** image 2**

### Using hostnamectl Command
To check kernel version in Linux we can use the hostnamectl command

hostnamectl

third image

This command provides information about the system's hostname and related settings. To check only the kernel version using the hostnamectl command, you can use the grep command to filter the output.

hostnamectl | grep 'Kernel:'

four image

### Using /proc/version File
The /proc/version file in Linux contains valuable information about the Linux kernel version, compiler details, and build information. It acts as a virtual file that you can access to obtain kernel-related data. To check kernel version in Linux we use to display the content of proc/version file. To check the kernel version in Linux using the /proc/version file, open a terminal and enter the following command:

cat /proc/version

The output will contain details on the Linux kernel version, the compiler version, and the build information.

five image

### Using dmesg Command
The dmesg command in Linux displays the kernel ring buffer messages. It enables you to see and analyze the system and kernel messages that are generated during the boot process or while the system is running. To check the kernel version in Linux using the dmesg command, open a terminal and enter the following command:

dmesg | grep Linux

image six
## Learn More (add links to related Scaler Topics articles)

[Linux Operating System](https://www.scaler.com/topics/linux-operating-system/)

[Basic Linux Commands with Examples](https://www.scaler.com/topics/linux-tutorial/linux-commands/)

[What are the Top Advantages and Disadvantages of Linux?](https://www.scaler.com/topics/advantage-and-disadvantage-of-linux/)

[Linux System Admin Commands](https://www.scaler.com/topics/linux-tutorial/cron-job-scheduling)

[Linux Cron Cheat Sheet](https://www.scaler.com/topics/cron-job-in-linux/)

## Conclusion (in points)

To check the kernel version in Linux, you can use the following methods:

* Using the uname command:
* Run `uname -r` to display the kernel version.
* Run `uname -a` for more detailed information about the kernel, including the release date and system architecture.
* Using the hostnamectl command:
* Run `hostnamectl` to view system information, including the kernel version.
* Run `hostnamectl | grep 'Kernel:'` to display only the kernel version.
* Using the /proc/version file:
* Run cat `/proc/version` to view the kernel version, compiler version, and build information.
* Using the dmesg command:
* Run `dmesg | grep Linux` to filter the output and display the kernel version from the kernel ring buffer messages.

## MCQ

1. Which command can be used to check the Linux kernel version?
1. uname -r
1. uname -a
1. hostnamectl
1. All of above
Correct Answer: 4
1. Which command provides additional details about the kernel, including release date and system architecture?

1. uname -r
1. uname -a
1. hostnamectl
1. None of the above
Correct Answer: 2
1. What does the major version number of the Linux kernel represent?
1. Incremental updates and bug fixes
1. New hardware support
1. Major architectural changes and new features
1. Security patches and stability improvements
Correct Answer: 3