200-901: Automating Networks Using Cisco PlatformsDemo

Question

Refer to the exhibit.

Question Image

What function does the EXPOSE line perform when an image is built from this Dockerfile?

A Local port 8080 of the container that launched with this docker image is accessible from co-hosted containers and external clients.
B Local port 8080 is not reachable at all because no IP address is specified along with the EXPOSE command of the Dockerfile.
C Local port 8080 is accessible from other containers running on the same docker host as the container that launched with this docker image.
D Local port 8080 of the container that launched with this docker image is accessible to external clients.

Explanation

EXPOSE 8080 declares TCP port 8080 as a port on which the container is expected to listen. It does not publish the port to the host or make it externally reachable; host-to-container access requires runtime port publishing, such as -p. Containers that can communicate over the Docker network can use the container port directly.

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Dockerfile reference — EXPOSE

200-901: Automating Networks Using Cisco PlatformsDemo

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