Remote access to webserver in docker container

Question

I\'ve started using docker for dev, with the following setup:

• Host machine - ubuntu server.
• Docker container - webapp w/ tomcat server (using https).<

Answer 1

If your container was built with a Dockerfile that has an EXPOSE statement, e.g. EXPOSE 443, then you can start the container with the -P option (as in "publish" or "public"). The port will be made available to connections from remote machines:

$ docker run -d -P mywebservice

If you didn't use a Dockerfile, or if it didn't have an EXPOSE statement (it should!), then you can also do an explicit port mapping:

$ docker run -d -p 80 mywebservice

In both cases, the result will be a publicly-accessible port:

$ docker ps
9bcb… mywebservice:latest … 0.0.0.0:49153->80/tcp …

Last but not least, you can force the port number if you need to:

$ docker run -d -p 8442:80 mywebservice

In that case, connecting to your Docker host IP address on port 8442 will reach the container.