Modern System Administration

Chapter 1. Patterns and Interconnections

Imagine you are making a cake with a friend. You followed the recipe, mixing all the ingredients (oil, flour, eggs, and sugar), and it looks OK, but when you taste it, something isn’t quite right. To be an accomplished baker, you must understand all the elements of a cake (ratios of flour to fat, etc.) and how they work together to impact the finished product’s quality (e.g., taste and texture). For example, in Figure 1-1, our bakers didn’t understand that sesame oil wasn’t an appropriate oil to include in the cake.

Now replace baker with sysadmin, and replace the golden ratios of a baker’s ingredients with the interconnected components in your system (e.g., smartphones, embedded devices, large servers, and storage arrays). To be an accomplished sysadmin, you need to understand how the components connect in common patterns and impact your system’s quality (e.g., reliability, scalability, and maintainability).

In this chapter, I will help you reason about your systems to see the patterns and interconnections in them so that you understand what informed the choices behind your system’s design.

Figure 1-1. Modeling understanding a system (image by Tomomi Imura)

How to Connect Things

Engineers choose architecture patterns, the reusable solutions to address typical workloads (e.g., batch processing, web servers, and caching). These patterns ...