How to Check Your Ubuntu and Linux Version (5 Quick Methods)

Method 1: cat /etc/os-release (Recommended)

This is the most reliable method on any modern Linux distribution. The /etc/os-release file is standardised across distros and always present on systems using systemd.

cat /etc/os-release

Example output on Ubuntu 24.04 (first lines; the file continues with URLs and UBUNTU_CODENAME):

PRETTY_NAME="Ubuntu 24.04.1 LTS"
NAME="Ubuntu"
VERSION_ID="24.04"
VERSION="24.04.1 LTS (Noble Numbat)"
VERSION_CODENAME=noble
ID=ubuntu
ID_LIKE=debian

Key fields:

• PRETTY_NAME — the human-readable full name and version
• VERSION_ID — just the version number (useful in scripts)
• ID — the distro identifier in lowercase (ubuntu, debian, fedora, centos)
• ID_LIKE — the parent distro family (debian, rhel, suse)

Pro tip: Use this in scripts to handle distro-specific logic:

source /etc/os-release
echo "Running on $NAME $VERSION_ID"

if [ "$ID" = "ubuntu" ]; then
    apt update
elif [ "$ID" = "fedora" ]; then
    dnf update
fi

Method 2: lsb_release -a

The LSB (Linux Standard Base) release command gives a clean, formatted output. It comes pre-installed on Ubuntu and Debian. On other distros you may need to install the lsb-release package first.

lsb_release -a

Example output:

Distributor ID: Ubuntu
Description:    Ubuntu 24.04.1 LTS
Release:        24.04
Codename:       noble

Useful flags:

• lsb_release -d — description only (one line)
• lsb_release -r — release number only
• lsb_release -c — codename only
• lsb_release -i — distributor ID only

If you get command not found on Debian or Ubuntu, install it:

# Debian/Ubuntu
sudo apt install lsb-release

On RHEL 9 and its rebuilds (Rocky, AlmaLinux) the old redhat-lsb-core package that used to provide lsb_release is no longer shipped, so use cat /etc/os-release there instead.

Method 3: uname -a (Kernel Version)

The uname command works on every Linux and Unix system ever made. It shows the kernel version rather than the distribution version, but it is universally available.

uname -a

Example output on the same Ubuntu 24.04 server (the build date after PREEMPT_DYNAMIC varies by kernel build):

Linux webserver01 6.8.0-45-generic #45-Ubuntu SMP PREEMPT_DYNAMIC [build date] x86_64 x86_64 x86_64 GNU/Linux

Breaking that down:

• Linux — kernel name
• webserver01 — hostname
• 6.8.0-45-generic — kernel version (Ubuntu 24.04 shipped with the 6.8 kernel; later point releases can move to a newer hardware-enablement kernel)
• #45-Ubuntu — build info (often hints at the distro)
• x86_64 — CPU architecture (important for Docker images and package selection); it is repeated for machine, processor and hardware platform

Useful flags:

• uname -r — kernel release only
• uname -m — machine architecture only (x86_64, aarch64, armv7l)
• uname -n — hostname only

When this matters: Kernel version is critical when troubleshooting driver issues, checking if a security patch has been applied, or verifying compatibility with software that requires a minimum kernel version (like Docker, WireGuard, or eBPF tools).

Method 4: hostnamectl

On any system running systemd (which is virtually every modern distro), hostnamectl gives you a clean summary of both OS and hardware information.

hostnamectl

Example output (trimmed; recent versions also show hardware vendor, model and firmware lines):

 Static hostname: webserver01
       Icon name: computer-vm
         Chassis: vm
      Machine ID: a1b2c3d4e5f6...
         Boot ID: f6e5d4c3b2a1...
  Virtualization: kvm
Operating System: Ubuntu 24.04.1 LTS
          Kernel: Linux 6.8.0-45-generic
    Architecture: x86-64

This is particularly useful because it also shows:

• Chassis — whether you are on a VM, container, physical server, or laptop
• Virtualization — the hypervisor type (kvm, vmware, microsoft, oracle, xen)
• Architecture — CPU architecture in a readable format

This is the command to use when you need to quickly understand what kind of machine you are on, not just what OS it runs.

Method 5: cat /etc/issue

The /etc/issue file contains the text displayed on the login screen before you authenticate. It usually shows the distro name and version.

cat /etc/issue

Example output:

Ubuntu 24.04.1 LTS \n \l

The \n and \l are escape codes for hostname and terminal line that get replaced on the actual login screen.

Warning: Some organisations customise this file with legal banners or security warnings, replacing the version info. It is also sometimes empty on minimal or container images. Use /etc/os-release as your primary method and fall back to this if needed.

Which Method Should You Use?

Bonus: Check Version in Docker Containers

Inside Docker containers, many of these files are stripped down. The most reliable approach:

# From outside the container
docker exec my-container cat /etc/os-release

# Inside the container
cat /etc/os-release

uname -a inside a container shows the host kernel, not the container’s OS. This catches people out. Use /etc/os-release for the container’s base image info.

Why This Matters for Your Career

Checking the OS version is one of the first things you do when:

• SSH’ing into an unfamiliar server for the first time
• Writing scripts that need to work across distros
• Troubleshooting package availability (packages differ between Ubuntu, Debian, RHEL)
• Verifying security patches are applied
• Documenting infrastructure for handover or audit
• Checking if a server meets minimum requirements for new software

It is a basic skill, but knowing which command to use and why is what separates someone who Googles it every time from someone who just knows.

Next Steps

Now you know what you are running, put that knowledge to use:

• Scripting Fundamentals — automate tasks with Bash and PowerShell
• Linux Fundamentals Series — the complete guide from basics to job-ready
• Cron and Task Scheduler — schedule your scripts to run automatically