What to do if a container in Docker crashes?

If a Docker container crashes, several steps should be taken for diagnosis and recovery:

1. Check the container status:

docker ps -a | grep <container_id_or_name>

2. View the container logs to understand the cause of the crash:

docker logs <container_id_or_name>

3. If the cause is clear (e.g., an application error), fix it and rebuild the image or change the configuration.

4. Restart the container:

docker start <container_id_or_name>

5. For automatic recovery, you can use Docker restart policy, for example:

docker run --restart unless-stopped ...

6. If the container crashes due to resource issues, check the load on the host and resource limits, and possibly increase them.

7. For complex problems, use monitoring and debugging tools, such as connecting inside the container via docker exec for additional analysis.