📚 How to update your Docker containers safely

Purpose

Learn how to update your Docker containers safely, minimizing downtime and preventing accidental data loss.

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1. Check Running Containers

List all currently running containers to know what services are active:

docker ps

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2. Pull the Latest Images

For each image you want to update, pull the latest version from the registry:

docker pull imagename:tag

Replace imagename:tag with your actual image name and tag.

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3. Stop and Remove Old Containers

Stop the container without deleting its data volumes:

docker stop containername
docker rm containername

Replace containername with your actual container name.

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4. Start New Containers with Updated Images

Use your original docker run command or your docker-compose file to launch the updated containers.

docker run -d --name containername imagename:tag

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5. Verify Everything is Working

After starting the new containers, check that everything is healthy:

docker ps
docker logs containername

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✅ Summary

• Always backup your data volumes before updating if possible.
• Use versioned tags (e.g., nginx:1.25) instead of latest to avoid unexpected changes.
• Use compose files to automate container recreation safely.