4 Ways to Check CentOS or RHEL Version

If you're using CentOS or RHEL (Red Hat Enterprise Linux), knowing your system version is essential for package management, troubleshooting, and security updates. There are several reliable methods to determine which version you're running.

This article covers four effective methods to check your CentOS or RHEL version, each with step-by-step instructions and example outputs.

Method 1: Check /etc/redhat-release File

The /etc/redhat-release file contains version information about your CentOS or RHEL system, including the release number and update level. This is the most straightforward method.

To check the contents of the /etc/redhat-release file:

cat /etc/redhat-release

Example output for CentOS:

CentOS Linux release 7.9.2009 (Core)

Example output for RHEL:

Red Hat Enterprise Linux Server release 8.4 (Ootpa)

Method 2: Use hostnamectl Command

The hostnamectl command displays comprehensive system information including hostname, kernel version, architecture, and operating system version. This command is available on systemd-based systems (RHEL 7+ and CentOS 7+).

hostnamectl

Example output:

   Static hostname: myserver.example.com
         Icon name: computer-server
           Chassis: server
        Machine ID: 123456789abcdef123456789abcdef12
           Boot ID: fedcba9876543210fedcba9876543210
  Operating System: CentOS Linux 7 (Core)
       CPE OS Name: cpe:/o:centos:centos:7
            Kernel: Linux 3.10.0-1160.45.1.el7.x86_64

The Operating System line shows your CentOS or RHEL version clearly.

Method 3: Use lsb_release Command

The lsb_release command displays Linux Standard Base (LSB) information including distributor ID, release number, and description. Note that this command may require installing the redhat-lsb-core package first.

lsb_release -a

Example output for CentOS:

LSB Version:    :core-4.1-amd64:core-4.1-noarch
Distributor ID: CentOS
Description:    CentOS Linux release 7.9.2009 (Core)
Release:        7.9.2009
Codename:       Core

If lsb_release is not installed, install it with:

yum install redhat-lsb-core

Method 4: Use rpm Command

The rpm command can query the release package to determine your system version. This method works by checking the installed release package.

For CentOS:

rpm -q centos-release

For RHEL:

rpm -q redhat-release

Example output for CentOS:

centos-release-7-9.2009.1.el7.centos.x86_64

Example output for RHEL:

redhat-release-server-8.4-1.el8.x86_64

Comparison of Methods

Additional Tips

You can also use these alternative methods:

• Kernel version: Use uname -r to check the kernel version, which can indicate your OS version

• OS information: Use cat /etc/os-release for detailed OS information on newer systems

• System information: Use cat /proc/version for comprehensive system and kernel details

Conclusion

These four methods provide reliable ways to check your CentOS or RHEL version. The /etc/redhat-release file method is the quickest, while hostnamectl provides the most comprehensive system information. Choose the method that best fits your needs and system configuration.