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      • Install Docker on Ubuntu

      This chapter covers how to install and configure Docker Engine on Ubuntu.

      System Requirements

      Docker Engine supports the following Ubuntu versions (64-bit):

      • Ubuntu 24.04 (Noble)
      • Ubuntu 22.04 (Jammy)
      • Ubuntu 20.04 (Focal)

      Hardware requirements: 64-bit processor, kernel 3.10+, at least 2GB RAM (4GB+ recommended).

      Uninstall Old Versions

      sudo apt-get remove docker docker-engine docker.io containerd runc

      1. Update and Install Dependencies

      sudo apt-get update
sudo apt-get install ca-certificates curl gnupg

      2. Add Docker's Official GPG Key

      sudo install -m 0755 -d /etc/apt/keyrings
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg
sudo chmod a+r /etc/apt/keyrings/docker.gpg

      3. Add Docker APT Repository

      echo \
  "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/ubuntu \
  $(. /etc/os-release && echo "$VERSION_CODENAME") stable" | \
  sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

      4. Install Docker Engine

      sudo apt-get update
sudo apt-get install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin

      5. Verify Installation

      sudo docker run hello-world

      Method 2: Convenience Script

      curl -fsSL https://get.docker.com -o get-docker.sh
sudo sh get-docker.sh

      ⚠️ The convenience script is not recommended for production environments.

      Post-Installation Setup

      Run Docker Without sudo

      sudo groupadd docker
sudo usermod -aG docker $USER
newgrp docker
docker run hello-world

      Enable Docker on Boot

      sudo systemctl enable docker.service
sudo systemctl enable containerd.service

      Configure Docker Daemon

      sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<EOF
{
  "log-driver": "json-file",
  "log-opts": {
    "max-size": "10m",
    "max-file": "3"
  },
  "storage-driver": "overlay2"
}
EOF
sudo systemctl restart docker

      Common Issues

      Permission Denied

      sudo chmod 666 /var/run/docker.sock
# Or verify user is in docker group
groups $USER

      Service Won't Start

      sudo systemctl status docker
sudo journalctl -xu docker.service

      Uninstall Docker

      sudo apt-get purge docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin
sudo rm -rf /var/lib/docker
sudo rm -rf /var/lib/containerd

      Further Reading