Install Docker on Mac

Follow the instruction here to download the docker dmg on mac and start it.

Start Docker Machine on Mac

Build Your Own Image

Use Docker Commit

• Build on top of an image without Dockerfile

Use Dockerfile

• it provides effective way to build an image
• easily fits into your continuous integration and deployment

Dockerfile

• each RUN will execute the command on the top writable layer and perform commit of the image
• you can aggregate multiple RUN by using && to avoid this overhead
• you can use “apt-get install -y” to answer yes to the questions as you cannot see the prompt.

Build an image from the Dockerfile

Single command instead of 2

• You will cut the steps above from 4 to 3 if you chain the command together using &&

CMD vs ENTRYPOINT

• CMD defines what command to run if you don’t override thru command option during “docker run”
• ENTRYPOINT can be used instead of CMD but ENTRYPOINT is not overridable. If you pass command option during docker run, ENTRYPOINT command will run before it.
• You can use ENTRYPOINT if you want to take argument from users. Use EXEC form is preferred as shell form cannot accept arguments at runtime.
• EXPOSE will expose the ports from container to ports of host.
• Build the image thru docker file

Build an image with intermediate images