How do I find out my Linux kernel version? How can I find the kernel version at shell prompt on Linux?

Linux stores version information in a file called /proc/version. As a sysadmin you need to know the version number of the Linux kernel on given server or workstation. This information can be used for the following purpose:

1. To fix device driver issue.
2. Install correct driver for NIC/RAID card.
3. Diagnosing system.
4. Upgrading system and more.

Howto: Find the kernel version

You need to type the following command at shell prompt:
$ uname -r
Sample outputs:

2.6.18-194.3.1.el5

The following command gives out more information:
$ cat /proc/version
Sample outputs:

Linux version 2.6.18-194.3.1.el5 (mockbuild@x86-004.build.bos.redhat.com) (gcc version 4.1.2 20080704 (Red Hat 4.1.2-48)) #1 SMP Sun May 2 04:17:42 EDT 2010

Please note that you can also use the following command:
$ uname -a
Sample outputs:

Linux b1 3.2.0-51-generic #77-Ubuntu SMP Wed Jul 24 20:18:19 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux

More About Linux Kernel Version Release Numbers Between 1.0 and 2.6.x

The Linux kernel used odd minor version numbers to denote development releases and even minor version numbers to denote stable releases; For example, Linux kernel version 2.3 was a development version and Linux 2.4 was the stable version. Since 2004 release of the v2.6 kernel, Linux no longer uses this system, and has a much shorter release cycle, instead now simply incrementing the third number, using a fourth number as necessary.

Related media

This tutorial is also available in a quick video format:

Video 01: Find The Linux Kernel Version Command Tutorial