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Showing posts from 2018

Docker: Run as non root user

It's good practice to run processes within a container as a non-root user with restricted permissions.  Even though containers are isolated from the host operating system, they do share the same kernel as the host. Also, processes within a container should be prevented from writing to where they shouldn't be allowed to as extra protection against exploitation. Running a Docker process as a non-root user has been a Docker feature as of version 1.10. To run a Docker process as a non-root user, permissions need to be accounted for meticulously.  This permission adjustment needs to be done when building a Dockerfile. You need to be aware of where in the filesystem your app might write to, and adjust the permissions accordingly.  Since everything in a container is considered disposable, the container process really shouldn't be writing to too many locations once build. Here is an annotated example of how you might create a Dockerfile where the process that runs within runs a