Linux is a powerful operating system with many robust networking constructs. Much like any networking technology, they are powerful individually but become much more powerful when combined in creative ways. Docker is a great example of a tool that combines many of the individual components of the Linux network stack into a complete solution. While Docker manages most of this for you, it's still helpful to know your way around when looking at the Linux networking components that Docker uses.
In this chapter, we'll spend some time looking at these constructs individually outside of Docker. We'll learn how to make network configuration changes on Linux hosts and validate the current state of the network configuration. While this chapter is not dedicated to Docker itself, it is important to understand the primitives for later chapters, where we discuss how Docker uses these constructs to network containers.