In this recipe, we will learn Docker configurations that may result in slightly improved security for your containers. Docker uses some advanced features in the latest Linux kernel, which include kernel namespaces to provide process isolation, control groups to control resource allocation, and kernel capabilities and user namespaces to run unprivileged containers. As stated on the Docker documentation page, Docker containers are, by default, quite secure.
This recipe covers some basic steps to improve Docker security and reduce the attack surface on the Ubuntu host as well as the Docker daemon.
The first and most common thing is to use the latest versions of your software. Make sure that you are using the latest Ubuntu version with all security updates applied and that your Docker version is the latest stable version:
Upgrade your Ubuntu host with the following commands:
$ sudo apt-get update $ sudo apt-get upgrade
If you used a Docker-maintained repository...