Chapter 1. Introduction to the CoreOS family
This chapter covers
- Overview of CoreOS systems and concepts
- Understanding common workflow patterns for CoreOS
- Introducing fleet and etcd, and systemd units
Suppose you’ve been hired by a new company that wants you to build out a modern infrastructure and operational architecture for its developers. The company has a wide range of application stacks, and you have strong requirements around horizontal scalability and high availability. You know you want Linux, but the idea of maintaining endless operating system updates and changes or setting up complex configuration-management systems is unappealing. You recognize that containerization can make this far easier—you can separate the operational configuration from the applications’—but you’re still left with how to manage all those containers at scale. Plenty of distributions today support Docker, but not in a way that seems designed for large-scale production use.
Enter CoreOS: an OS designed from the ground up to facilitate container operationalization at any scale. It’s highly fault tolerant and extremely lightweight, and it appears performant, but how do you get started? You know the goal: you want to provide your engineers with a container-based platform as a service, and you know CoreOS can be the hammer to hit that nail. But how do you get it running? How do you adapt or design application architectures to best take advantage of this system?