База знаний

Keeping Docker Engine and Compose updated brings security fixes, performance improvements, and compatibility with newer image features. This guide covers updating safely without disrupting running containers.

Prerequisites

• Docker Engine installed via the official repository
• Root or sudo access

Step 1 — Check Current Versions

docker --version
docker compose version

Step 2 — Refresh Package Information

sudo apt update

Step 3 — Upgrade Docker Packages

sudo apt install --only-upgrade docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin -y

Step 4 — Restart the Docker Service

sudo systemctl restart docker

Restarting the Docker daemon does not stop containers configured with a restart policy — they typically resume automatically, but briefly interrupt network connections during the restart.

Step 5 — Verify

docker --version
docker compose version
docker ps

Step 6 — Update Your Application Images

Updating Docker itself does not update the images your containers run. Pull the latest versions separately:

cd /path/to/your/project
docker compose pull
docker compose up -d

Compose will recreate only the containers whose images actually changed.

Step 7 — Clean Up Old Images and Unused Resources

docker system df
docker image prune -a
docker volume prune
docker network prune

docker image prune -a removes all unused images — confirm you don't need any of them cached locally before running it.

Common Errors

Packages held back:

sudo apt update
sudo apt full-upgrade -y

Containers don't start after update — check logs:

docker compose logs

Best Practices

• Create a snapshot or backup before major version updates on production systems
• Update during a scheduled maintenance window
• Review Docker's release notes for breaking changes before major upgrades
• Update images and Docker Engine on a regular schedule, not just reactively

FAQ

Will updating Docker delete my containers or volumes?
No — updating the Docker Engine package does not remove existing containers, images, or volumes.

How often should I update Docker?
Check monthly at minimum, and apply security-related releases promptly.

Related Articles

• How to Install Docker Engine on Ubuntu & Debian
• Docker Compose Troubleshooting: Common Errors & Fixes
• Docker Security Best Practices