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Using ephemeral mapping

After setting up a few container instances with specific port mappings, your team's QA member would like to know how to automatically map an ephemeral port to a container for testing. They'd like to make sure multiple container instances can be mapped without modifying the Docker command being used.

This exercise is part of the course

Intermediate Docker

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Exercise instructions

  • Update the Dockerfile to expose port 8000, replacing the ____ characters.
  • Rebuild the image with the tag named qaserver.
  • Run the proper docker command to automatically map the container to an ephemeral port. You may also wish to use the -d flag to detach Docker from the terminal.
  • Use the docker ps command to check the ports being used.

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