Chapter 10
Control Plane

In the preceding chapters we worked our way up from bare metal through layers of abstraction and virtualization to create a sea of instances running on machines. We’ve got software scattered around like an upended box of LEGO blocks. It’s up to the “control plane” to put these pieces in the right place and knit them together into a somewhat coherent whole.

The control plane encompasses all the software and services that run in the background to make production load successful. One way to think about it is this: if production user data passes through it, it’s production software. If its main job is to manage other software, it’s the control plane.

A challenge we’ll face in this chapter is that the solution space is not well partitioned among tools, packages, and vendors. It’s nowhere near as simple as picking one download from each column. There are overlaps and gaps. Not every combination will work together. No single package does everything. We are left with a lot of integration effort and plenty of trial and error.