Linux Command: Show Linux Version

What command I need to type to display Linux kernel version and other information such as Linux distribution name? How do I check Linux kernel version number?

You need to use the following two commands:
[a] uname - Print kernel and system information.

[b] lsb_release - Print distribution-specific information.
[c] /proc/version file - Print running kernel information.

How to check linux kernel version number?

Open a shell prompt (or a terminal) and type the following command to see your current Linux kernel version:
$ uname -r

Sample outputs:

2.6.32-23-generic-pae

Or type the following command:
$ uname -mrs

Sample outputs:

Linux 2.6.32-23-generic-pae i686

To print all information, enter:
$ uname -a

Sample outputs:

Linux vivek-laptop 2.6.32-23-generic-pae #37-Ubuntu SMP Fri Jun 11 09:26:55 UTC 2010 i686 GNU/Linux

Where,

• 2.6.32-23 - Linux kernel version number
• pae - pae kernel type indicate that I'm accssing more than 4GB ram using 32 bit kernel.
• SMP - Kernel that supports multi core and multiple cpus.

/proc/version file

Type the following command to see Linux version info:
$ cat /proc/version 


Sample outputs:

Linux version 3.2.0-0.bpo.1-amd64 (Debian 3.2.4-1~bpo60+1) (ben@decadent.org.uk) (gcc version 4.4.5 (Debian 4.4.5-8) ) #1 SMP Sat Feb 11 08:41:32 UTC 2012

The above output identifies the kernel version that is currently running. It includes the contents of /proc/sys/kernel/ostype, /proc/sys/kernel/osrelease, and /proc/sys/kernel/version files.

For example:
$ cat /proc/sys/kernel/{ostype,osrelease,version} 

Sample outputs:

Linux
3.2.0-0.bpo.1-amd64
#1 SMP Sat Feb 11 08:41:32 UTC 2012

Find Distribution Version

Type the following command:
$ cat /etc/*release

OR

$ lsb_release -a

Sample outputs:

No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 10.04 LTS
Release: 10.04
Codename: lucid

Here is another output from my Debian based server:

lsb_release -a

No LSB modules are available.
Distributor ID: Debian
Description: Debian GNU/Linux 6.0.6 (squeeze)
Release: 6.0.6
Codename: squeeze

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