ENTRYPOINT vs CMD difference in Docker - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the Dockerfile line to set the default command using CMD.

Docker

CMD ["[1]"]

Drag options to blanks, or click blank then click option'

ACOPY

BRUN

CENTRYPOINT

Dbash

Attempts:

3 left

💡 Hint

Common Mistakes

Using RUN instead of CMD

Confusing ENTRYPOINT with CMD

The CMD instruction sets the default command to run when the container starts, such as bash.

2fill in blank

medium

Complete the Dockerfile line to set the container's main executable using ENTRYPOINT.

Docker

ENTRYPOINT ["[1]"]

Drag options to blanks, or click blank then click option'

ACOPY

BCMD

Cpython

DRUN

Attempts:

3 left

💡 Hint

Common Mistakes

Using CMD instead of ENTRYPOINT

Using Dockerfile commands like COPY here

ENTRYPOINT sets the main executable for the container, like python to run Python scripts.

3fill in blank

hard

Complete the docker run command to override the CMD arguments and echo 'World' instead.

Docker

ENTRYPOINT ["/bin/sh", "-c"]
CMD ["echo Hello"]
# To override CMD, use: docker run myimage [1]

Drag options to blanks, or click blank then click option'

Aecho World

B--entrypoint echo World

C--cmd echo World

D--rm

Attempts:

3 left

💡 Hint

Common Mistakes

Using --entrypoint, which overrides the ENTRYPOINT instead

Using invalid --cmd option

Confusing --rm with command override

CMD provides default arguments to the ENTRYPOINT, which can be overridden by simply passing arguments after the image name in docker run: docker run myimage echo World executes /bin/sh -c echo World.

4fill in blank

hard

Fill both blanks to create a Dockerfile snippet where ENTRYPOINT runs python and CMD passes the script name.

Docker

ENTRYPOINT ["[1]"]
CMD ["[2]"]

Drag options to blanks, or click blank then click option'

Apython

Bapp.py

Cbash

Dscript.sh

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping ENTRYPOINT and CMD values

Using bash instead of python for ENTRYPOINT

ENTRYPOINT runs python and CMD provides the default script app.py to run.

5fill in blank

hard

Fill all three blanks to write a Dockerfile snippet where ENTRYPOINT runs /bin/bash, CMD passes -c, and default command echoes Hello.

Docker

ENTRYPOINT ["[1]"]
CMD ["[2]", "[3]"]

Drag options to blanks, or click blank then click option'

A/bin/bash

B-c

Cecho Hello

D/bin/sh

Attempts:

3 left

💡 Hint

Common Mistakes

Using /bin/sh instead of /bin/bash

Missing the -c option for bash

ENTRYPOINT runs /bin/bash, CMD passes -c and the command echo Hello to execute.