Docker simplifies application deployment with containerization. Running Docker without root enhances security and streamlines workflows. This guide will walk you through installing Docker on Linux and configuring it for non-root usage.

Prerequisites

  • A Linux system (Ubuntu, Debian, CentOS, etc.)
  • A user account with sudo privileges.

1. Update Your System

Keeping your system updated ensures compatibility and security.

For Ubuntu/Debian:

sudo apt update && sudo apt upgrade -y

For RHEL-based systems (e.g., CentOS):

sudo yum update -y

2. Install Docker

Docker installation steps vary slightly between Linux distributions.

For Ubuntu/Debian

  1. Install prerequisite packages:

    sudo apt install -y apt-transport-https ca-certificates curl software-properties-common

  2. Add Docker’s official GPG key:

    curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg

  3. Set up the Docker repository:

    echo "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

  4. Install Docker:

    sudo apt update
sudo apt install -y docker-ce docker-ce-cli containerd.io

For RHEL/CentOS

  1. Install prerequisite packages:

    sudo yum install -y yum-utils

  2. Set up the Docker repository:

    sudo yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo

  3. Install Docker:

    sudo yum install -y docker-ce docker-ce-cli containerd.io

3. Start and Enable Docker

Start the Docker service:

sudo systemctl start docker

Enable Docker to start on boot:

sudo systemctl enable docker

4. Verify Docker Installation

Run a test to confirm Docker is installed correctly:

sudo docker run hello-world

You should see a message indicating Docker is running successfully.

5. Configure Docker for Non-Root Usage

To run Docker commands without sudo, follow these steps:

  1. Add your user to the Docker group:

    sudo usermod -aG docker $USER

  2. Log out and log back in for the group changes to apply.

  3. Verify non-root access:

    docker run hello-world

If the command runs successfully, Docker is now configured for non-root usage.

Additional Tips

  • Check Docker Version:

    docker --version

  • Manage Docker as a Service:

    • Restart Docker: sudo systemctl restart docker
    • Stop Docker: sudo systemctl stop docker

  • Uninstall Docker (if needed): For Ubuntu/Debian:

    sudo apt remove -y docker-ce docker-ce-cli containerd.io

    For RHEL/CentOS:

    sudo yum remove -y docker-ce docker-ce-cli containerd.io

Conclusion

Congratulations! Docker is now installed on your Linux system and can be used without root privileges. Enjoy secure and efficient containerized application development! 🚀

For more tutorials and guides, stay tuned to this blog. Have questions? Drop them in the comments below!