Docker Docker Images and Containers Running vs Exited Containers Autoremoval --rm Interactive Mode -it Detached Mode -d

1. Running vs Exited Containers, Auto-removal (--rm), Interactive Mode (-it), Detached Mode (-d)

Understand the lifecycle of containers and how to manage them with flags.

docker run

2. Step-by-Step

1. Start a new container from an image: docker run -it ubuntu /bin/bash
2. Check the container is running: docker ps
3. Output: Container ID and image name
4. ⚠️ Stop the container: docker stop <container_id>
5. Check the container is stopped: docker ps -a
6. Output: Container ID, image name, and status (exited)
7. ⚠️ Remove the stopped container: docker rm <container_id>
8. Check the container is removed: docker ps -a
9. Output: Container ID is no longer listed
10. Run a container with auto-removal: docker run --rm -it ubuntu /bin/bash
11. Check the container is removed after stopping: docker ps -a
12. Output: Container ID is no longer listed
13. Run a container in detached mode: docker run -d ubuntu /bin/bash
14. Check the container is running in detached mode: docker ps
15. Output: Container ID and image name
16. Run a container in interactive mode: docker run -it ubuntu /bin/bash
17. Check the container is running in interactive mode: docker ps
18. Output: Container ID and image name

3. Real Commands with Examples

1. Purpose: Run a container with auto-removal and interactive mode.
   Command: docker run --rm -it ubuntu /bin/bash
   Flags: --rm removes the container after stopping, -it enables interactive mode.
2. Purpose: Run a container in detached mode.
   Command: docker run -d ubuntu /bin/bash
   Flags: -d runs the container in detached mode.
3. Purpose: Run a container with a specific command.
   Command: docker run -it ubuntu ls -l
   Flags: -it enables interactive mode, ls -l runs the ls command with long format.

4. Common Errors

1. Error: docker: Error response from daemon: Container <container_id> is not running.
   Why: The container is stopped or removed.
   Fix: docker start <container_id> or docker run <image_name>.
2. Error: docker: Error response from daemon: Container <container_id> is not found.
   Why: The container is removed.
   Fix: docker run --rm <image_name>.
3. Error: docker: Error response from daemon: Container <container_id> is already running.
   Why: The container is already running.
   Fix: docker stop <container_id> and then docker rm <container_id>.

5. Quick Checks

1. Situation: Container is running and interactive.
   Command: docker ps
   Correct response: Container ID and image name.
2. Situation: Container is stopped and removed.
   Command: docker ps -a
   Correct response: Container ID is no longer listed.
3. Situation: Container is running in detached mode.
   Command: docker ps
   Correct response: Container ID and image name.

6. Last-Minute Reference

• ⚠️ --rm removes the container after stopping.
• docker run starts a new container.
• -it enables interactive mode.
• -d runs the container in detached mode.
• docker ps lists running containers.
• docker ps -a lists all containers.
• docker stop stops a container.
• docker rm removes a stopped container.
• docker start starts a stopped container.
• ? Verify with 'docker version' for changes in Docker versions.