Define, Build and Modify Container Images CKAD Practice Questions (Page 1)

Questions 1–5

1. 1foundation · easy

   A developer needs to modify an existing container image without changing its Dockerfile. Which approach allows this?

   • ARun a container from the image, make changes inside it, and use `docker commit` to create a new image.
   • BUse `docker cp` to copy files into the image file.
   • CUse `docker update` to modify the image directly.
   • DUse `docker export` to save the image and then re-import it with changes.
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2. 2expert · hard

   A developer needs to modify an existing image to include a new file /data/config.json. The developer does not have the original Dockerfile. The developer starts a container from the image, copies the file into the container, and then commits the changes. Which command correctly creates a new image with the changes?

   • Adocker export <container-id> | docker import - myapp:new
   • Bdocker commit <container-id> myapp:new
   • Cdocker save <container-id> -o myapp:new.tar
   • Ddocker cp <container-id>:/data/config.json myapp:new
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4. 3expert · hard

   A team is optimizing a Dockerfile for a Python application. The application has many dependencies listed in requirements.txt. The current Dockerfile copies the entire application source code before running pip install. The team notices that every source code change triggers a full reinstall of all dependencies, slowing down the build. Which change best improves build cache efficiency?

   • AUse a multi-stage build to compile dependencies in a separate stage.
   • BRun pip install with the --no-cache-dir flag.
   • CCombine the COPY and RUN pip install instructions into a single RUN instruction.
   • DCopy only requirements.txt first, run pip install, then copy the rest of the source code.
   Reveal Solution Discussion Select an answer first
5. 4foundation · easy

   What is the primary benefit of using a multi-stage build in a Dockerfile?

   • AIt reduces the final image size by discarding build-time dependencies and intermediate artifacts.
   • BIt speeds up the build by running multiple stages in parallel.
   • CIt automatically applies security patches to the base image.
   • DIt allows the image to run on multiple operating systems.
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6. 5application · medium

   A developer needs to run a container from an image that is stored in a private registry at registry.example.com. The developer has already logged in to the registry. The image is tagged as myapp:2.0. Which command correctly pulls and runs the image?

   • Adocker run myapp:2.0
   • Bdocker run registry.example.com/myapp:2.0
   • Cdocker pull myapp:2.0 && docker run registry.example.com/myapp:2.0
   • Ddocker pull registry.example.com/myapp:2.0 && docker run myapp:2.0
   Reveal Solution Discussion Select an answer first