Book Image

Argo CD in Practice

By : Liviu Costea, Spiros Economakis
Book Image

Argo CD in Practice

By: Liviu Costea, Spiros Economakis

Overview of this book

GitOps follows the practices of infrastructure as code (IaC), allowing developers to use their day-to-day tools and practices such as source control and pull requests to manage apps. With this book, you’ll understand how to apply GitOps bootstrap clusters in a repeatable manner, build CD pipelines for cloud-native apps running on Kubernetes, and minimize the failure of deployments. You’ll start by installing Argo CD in a cluster, setting up user access using single sign-on, performing declarative configuration changes, and enabling observability and disaster recovery. Once you have a production-ready setup of Argo CD, you’ll explore how CD pipelines can be built using the pull method, how that increases security, and how the reconciliation process occurs when multi-cluster scenarios are involved. Next, you’ll go through the common troubleshooting scenarios, from installation to day-to-day operations, and learn how performance can be improved. Later, you’ll explore the tools that can be used to parse the YAML you write for deploying apps. You can then check if it is valid for new versions of Kubernetes, verify if it has any security or compliance misconfigurations, and that it follows the best practices for cloud-native apps running on Kubernetes. By the end of this book, you’ll be able to build a real-world CD pipeline using Argo CD.
Table of Contents (15 chapters)
1
Part 1: The Fundamentals of GitOps and Argo CD
4
Part 2: Argo CD as a Site Reliability Engineer
7
Part 3: Argo CD in Production

Using the app of apps pattern

In Chapter 2, Getting Started with Argo CD, we created a quick example of the app of apps pattern while we were using Argo CD Autopilot. It’s also important to talk about how we would use the app of apps pattern in real environments and why we need it. In the previous section, we followed one step of the pattern by bootstrapping the cluster with Argo CD, but in a real environment, we want to create a repeatable K8s cluster with the same services; this is especially critical in disaster-recovery scenarios.

Why the app of apps pattern?

The pattern in practice gives us the ability to have a master application and logical grouping of another set of applications. You can create a master app that creates other apps and allows you to declaratively manage a group of apps that can be deployed in concert.

The pattern is used for bootstrapping a cluster with all the applications, and this is the main thing we are trying to accomplish in this chapter...