Prerequisites
- Sudo access
- Current package updates
- Enough disk space for images and application data
Security note
Membership in the docker group is effectively root-level access. Add only trusted administrators and do not expose the Docker daemon TCP socket publicly.
Step 1
Update the host
Install current operating system updates and review available disk space before adding container images.
sudo apt update
sudo apt upgrade
df -hStep 2
Choose a trusted package source
Use Ubuntu's maintained package or Docker's official repository instructions for your exact Ubuntu release. Verify repository keys and URLs against the vendor documentation before installation.
Step 3
Install and start Docker
The Ubuntu package provides the Docker engine. Package names and Compose availability can vary by supported release.
sudo apt install docker.io
sudo systemctl enable --now dockerStep 4
Verify the service
Check the daemon status and run a small test container before deploying application data.
sudo docker version
sudo docker run --rm hello-worldStep 5
Plan storage, logs, and updates
Use named volumes or bind mounts for persistent data, configure log rotation, and include images plus application data in the patching and backup plan.
Troubleshooting
- The daemon is not running
- Check systemctl status docker and journalctl -u docker for the first actionable error.
- The disk fills unexpectedly
- Inspect Docker disk usage, application logs, and unused images. Confirm data is backed up before pruning anything.
Frequently asked questions
Do containers replace backups?
No. Container images are reproducible software layers; persistent volumes, secrets, and configuration still require independent backups.