Does docker EXPOSE refer to the container port or the host port?

Question

The Dockerfile command EXPOSE and the docker run argument --expose tells docker that the port must be exposed.

When publishing ports with -p, you can map an outer host port to a different inner container port, e.g. docker run -p 8080:80, where 8080 is the host port and 80 is the container port.

My question is, does EXPOSE refer to the inner container port or the outer host port?

Answer 1

The EXPOSE instruction in a Dockerfile refers to the container port.