Docker Docker Troubleshooting docker logs docker inspect docker events

1. Core Command / Concept

View and manage Docker container logs, inspect container and image details, and monitor container events. docker logs, docker inspect, and docker events.

2. Step-by-Step (numbered)

1. Check if Docker is running: docker ps
2. Get logs from a running container named "my-web-server": docker logs my-web-server
3. Inspect a container named "my-web-server": docker inspect my-web-server
4. Inspect an image named "my-web-server": docker inspect my-web-server:latest
5. Get events from a container named "my-web-server": docker events --filter container=my-web-server
6. ⚠️ Delete all stopped containers: docker system prune -f
7. Clean up stopped containers: docker rm $(docker ps -aq -f status=exited)
8. Clean up unused images: docker rmi $(docker images -q -f dangling=true)

3. Real Commands with Examples

Example 1: Get logs from a container

Purpose: View logs from a running container.
Command: docker logs -f --tail 10 my-web-server Flags: - -f follows the log output - --tail 10 shows the last 10 lines of the log

Example 2: Inspect a container

Purpose: View detailed information about a container.
Command: docker inspect -f '{{.NetworkSettings.IPAddress}}' my-web-server Flags: - -f specifies the output format - {{.NetworkSettings.IPAddress}} shows the IP address of the container

Example 3: Get events from a container

Purpose: Monitor events from a container.
Command: docker events --filter container=my-web-server --since 1m Flags: - --filter container=my-web-server filters events by container name - --since 1m shows events from the last minute

4. Common Errors (3-5)

Error 1: No such container

Error message: Error: No such container: my-web-server Why it happens: The container does not exist.
One-line fix: docker ps to check if the container is running.

Error 2: Permission denied

Error message: Got permission denied while trying to connect to the Docker daemon socket Why it happens: Insufficient permissions to access the Docker socket.
One-line fix: sudo docker logs my-web-server

Error 3: Image not found

Error message: Error: image 'my-web-server:latest' not found Why it happens: The image does not exist.
One-line fix: docker images to check if the image is available.

5. Quick Checks (3 scenarios)

Scenario 1: Check if a container is running

Situation: You want to check if a container named "my-web-server" is running.
Command: docker ps -a --filter name=my-web-server Correct response: The container name should be listed.

Scenario 2: Check container logs

Situation: You want to check the logs of a container named "my-web-server".
Command: docker logs my-web-server Correct response: The logs should be displayed.

Scenario 3: Check container events

Situation: You want to check the events of a container named "my-web-server".
Command: docker events --filter container=my-web-server Correct response: The events should be displayed.

6. Last-Minute Reference

• docker logs flags: -f, --tail, --since
• docker inspect flags: -f, --format
• docker events flags: --filter, --since
• docker ps flags: -a, --filter
• docker images flags: -q, --filter
• docker rmi flags: -f
• docker rm flags: -f
• ⚠️ docker system prune deletes all stopped containers and unused images.
• ⚠️ docker rmi -f deletes an image without prompting for confirmation.
• ⚠️ docker rm -f deletes a container without prompting for confirmation.
• ⚠️ docker system prune -f deletes all stopped containers, unused images, and dangling volumes.