Inspecting container details in Docker - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

Inspecting container IP address

You run the command docker inspect -f '{{ .NetworkSettings.IPAddress }}' mycontainer. What is the expected output?

Docker

docker inspect -f '{{ .NetworkSettings.IPAddress }}' mycontainer

A Shows the container's mounted volumes

B Shows the container's image ID

C Shows the IP address assigned to the container named 'mycontainer'

D Shows the container's creation date

💡 Hint

The command uses a Go template to extract network info.

The command uses the Go template to extract the IP address from the container's network settings.

🧠 Conceptual

intermediate

Understanding docker inspect output format

What does the docker inspect command output by default?

A A JSON array with detailed information about the container or image

B A plain text summary of container logs

C A list of running processes inside the container

D The container's resource usage statistics

💡 Hint

Think about the data format used for detailed info.

By default, docker inspect outputs detailed info in JSON format.

❓ Troubleshoot

advanced

Troubleshooting missing container details

You run docker inspect mycontainer but get an error: Error: No such object: mycontainer. What is the most likely cause?

A Docker daemon is not running

B You do not have permission to run docker commands

C The docker inspect command syntax is incorrect

D The container named 'mycontainer' does not exist or is not running

💡 Hint

Check if the container name is correct and exists.

The error means docker cannot find a container with that name or ID.

✅ Best Practice

advanced

Extracting specific container info efficiently

Which command is best to get only the container's mount points using docker inspect?

A docker inspect mycontainer | grep Mounts

B docker inspect -f '{{ json .Mounts }}' mycontainer

C docker inspect -f '{{ .Config.Mounts }}' mycontainer

D docker inspect --format '{{ .HostConfig.Mounts }}' mycontainer

💡 Hint

Use the correct Go template field and format for mounts.

The '.Mounts' field contains mount info; using '{{ json .Mounts }}' outputs it as JSON.

🔀 Workflow

expert

Sequence to find container's exposed ports

Arrange the steps to find the exposed ports of a container named 'webapp' using docker commands.

A 1,3,2,4

B 1,2,3,4

C 3,1,2,4

D 2,1,3,4

💡 Hint

First get details, then extract with template, then interpret.

You first inspect, then extract ports with template, then interpret output.