6. Interpret Contents of a Dockerfile 200-901 Practice Questions (Page 7)

Questions 31–35

1. 31foundation · easy

   Which Dockerfile instruction creates a mount point for persistent data storage?

   • AWORKDIR
   • BEXPOSE
   • CVOLUME
   • DENV
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2. 32application · medium

   A containerized application writes log files to `/var/log/app`. The logs must persist even if the container is removed. The Dockerfile should declare a mount point for this directory. Which instruction should be added?

   • A`VOLUME /var/log/app`
   • B`EXPOSE /var/log/app`
   • C`ENV LOG_DIR=/var/log/app`
   • D`WORKDIR /var/log/app`
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4. 33foundation · easy

   Which Dockerfile instruction is used to declare that a container will listen on TCP port 8080?

   • APORT 8080
   • BLISTEN 8080
   • CPUBLISH 8080
   • DEXPOSE 8080
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5. 34foundation · easy

   Which of the following is a Dockerfile best practice to improve cache efficiency?

   • APlacing COPY instructions before RUN instructions
   • BCombining all RUN commands into one line
   • CUsing the `latest` tag for base images
   • DOrdering instructions from least to most frequently changing
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6. 35expert · hard

   A Dockerfile for a network monitoring agent uses `ENTRYPOINT ["/usr/bin/agent"]` and `CMD ["--config", "/etc/agent.conf"]`. The agent reads a configuration file path from the first command-line argument. A user needs to run the container with a different configuration file. Which `docker run` command should be used?

   • A`docker run image --entrypoint /usr/bin/agent --config /tmp/custom.conf`
   • B`docker run --entrypoint /usr/bin/agent image --config /tmp/custom.conf`
   • C`docker run image --config /tmp/custom.conf`
   • D`docker run image /usr/bin/agent --config /tmp/custom.conf`
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