install-docker.sh — Docker installer script

Purpose

• Installs Docker Engine, CLI, containerd and Compose plugin across common Linux distributions (Ubuntu/Debian, CentOS/RHEL, Fedora, Alpine, Arch).

Requirements

• A Linux system with one of the supported distributions.
• sudo privileges for the user running the script.
• Internet access to download packages from Docker repositories.

Usage

1. Make the script executable (if not already):

chmod +x install-docker.sh

2. Run the script as your normal user (you will be prompted for sudo):

./install-docker.sh

The script detects your OS via /etc/os-release and runs the appropriate package commands.

Post-install steps

• The script enables and starts the Docker service via systemctl.
• It also adds the current user to the docker group. You may need to log out and log back in (or run newgrp docker) to use Docker without sudo.

Notes & Troubleshooting

• Unsupported OS: the script exits with an error if the distribution is not recognized.
• On systems without systemd (or where systemctl is unavailable), service start/enable will fail—start Docker manually as appropriate for your init system.
• If package repository GPG fetch or keyring operations fail, verify network access and that curl/gnupg are present.
• The script assumes typical package managers: apt, yum, dnf, apk, or pacman.

Example

# Run installer (prompts for sudo)
./install-docker.sh

# Verify Docker
docker --version
sudo systemctl status docker

Security

• The script adds official Docker package repositories and installs upstream packages. Review the commands if you have custom security requirements.

Contributing / Changes

• To adapt the script for additional distributions or custom mirrors, add/modify the case branches that handle installation for each OS.

License

• No license included. If you want this README or script under a specific license, add a LICENSE file.