Book Image

Real-World SRE

By : Pavlos Ratis, Nat Welch
Book Image

Real-World SRE

By: Pavlos Ratis, Nat Welch

Overview of this book

Real-World SRE is the go-to survival guide for the software developer in the middle of catastrophic website failure. Site Reliability Engineering (SRE) has emerged on the frontline as businesses strive to maximize uptime. This book is a step-by-step framework to follow when your website is down and the countdown is on to fix it. Nat Welch has battle-hardened experience in reliability engineering at some of the biggest outage-sensitive companies on the internet. Arm yourself with his tried-and-tested methods for monitoring modern web services, setting up alerts, and evaluating your incident response. Real-World SRE goes beyond just reacting to disaster—uncover the tools and strategies needed to safely test and release software, plan for long-term growth, and foresee future bottlenecks. Real-World SRE gives you the capability to set up your own robust plan of action to see you through a company-wide website crisis. The final chapter of Real-World SRE is dedicated to acing SRE interviews, either in getting a first job or a valued promotion.
Table of Contents (16 chapters)
Real-World SRE
Contributors
Preface
Other Books You May Enjoy
Index

Sending an HTTP request


One of my favorite interview questions, which seems to be used by just about everyone, is to ask the interviewee to describe all of the steps of an HTTP request. There are lots of ways you could dig into this. I once had someone explain to me how the computer interprets keyboard presses. While that is fascinating, for now we will walk through the networking side of things.

Let's say you type natwelch.com/resume into your browser. We will go through all of the steps that happen for that to deliver content for your browser to render.

DNS

DNS (domain name system): Computers talk to each other using IP addresses and DNS translates a domain into an IP address. Technically, DNS does a little more than that, but let's start by describing domain names and go from there. In our example, natwelch.com is the domain and /resume is the path.

Figure 3: In all three of the above domains, natwelch on the left is the domain. In the first example, com is the TLD. In the second, uk is...