Book Image

Learning DevOps - Second Edition

By : Mikael Krief
Book Image

Learning DevOps - Second Edition

By: Mikael Krief

Overview of this book

In the implementation of DevOps processes, the choice of tools is crucial to the sustainability of projects and collaboration between developers and ops. This book presents the different patterns and tools for provisioning and configuring an infrastructure in the cloud, covering mostly open source tools with a large community contribution, such as Terraform, Ansible, and Packer, which are assets for automation. This DevOps book will show you how to containerize your applications with Docker and Kubernetes and walk you through the construction of DevOps pipelines in Jenkins as well as Azure pipelines before covering the tools and importance of testing. You'll find a complete chapter on DevOps practices and tooling for open source projects before getting to grips with security integration in DevOps using Inspec, Hashicorp Vault, and Azure Secure DevOps kit. You'll also learn about the reduction of downtime with blue-green deployment and feature flags techniques before finally covering common DevOps best practices for all your projects. By the end of this book, you'll have built a solid foundation in DevOps and developed the skills necessary to enhance a traditional software delivery process using modern software delivery tools and techniques.
Table of Contents (25 chapters)
1
Section 1: DevOps and Infrastructure as Code
7
Section 2: DevOps CI/CD Pipeline
11
Section 3: Containerized Microservices with Docker and Kubernetes
14
Section 4: Testing Your Application
18
Section 5: Taking DevOps Further/More on DevOps

Monitoring applications and metrics in Kubernetes

When we deploy an application in Kubernetes, it's very important—and I consider it a requirement—to have a monitoring strategy for checking and debugging the life cycle of these applications and checking the central processing unit (CPU) and random-access memory (RAM) metrics.

We will now discuss different ways to debug and monitor your applications in Kubernetes.

Let's start with the basic way, which is the use of the kubectl command line.

Using the kubectl command line

To debug applications with the kubectl command line, run the commands detailed next:

  • To display the state of Kubernetes resources, run the following command:
    kubectl get pods,svc

The output of the preceding command is shown in the following screenshot:

Figure 10.29 – kubectl getting resources

With this command, we can see if pods are running and find out about services' statuses.

...