Senior administration

This is the final part. You administer a server with confidence and want to see what happens under the hood. This part is deep Linux only: performance, kernel internals, a diagnosis method, security, storage, and disaster recovery. You already know the commands. Now you work out why the system behaves the way it does.

What you need. A virtual machine or a separate server you can afford to break. Most chapters need root, load tests, and edits to kernel parameters, so do not bring your working machine here. A snapshot before each chapter is your insurance.

How to read. Chapters go in order, each builds on the previous one. The "how it works" boxes are a second layer for those curious about how things work underneath; you can skip them and come back later. Each chapter ends with exercises and a short summary.