How to Update Docker Images: Methods Guide

There are several methods to update container images in Docker.

1. Rebuild the image: Create a new image by either modifying the Dockerfile or using different build commands, then use this new image to create a new container.
2. With the Docker commit command, you can make changes or modifications within a container, and then use the docker commit command to save those changes as a new image. For example, using docker commit will save the container’s changes as a new image.
3. To update a Docker image: Use the Docker pull command to fetch the updated image, then stop and remove the old container, and finally create a new container using the new image. For example, use docker pull to get the updated image, then use docker stop to halt the old container, docker rm to delete the old container, and lastly use the docker run command to create a new container.
4. Rolling updates can be conducted using Docker swarm or Kubernetes for container orchestration purposes, ensuring a seamless update process by replacing containers one by one without interrupting services.

Regardless of the method used to update the container image, it is important to ensure that the new image is compatible with the old one and that the updated container can run properly.