Book Image

Mastering KVM Virtualization - Second Edition

By : Vedran Dakic, Humble Devassy Chirammal, Prasad Mukhedkar, Anil Vettathu
Book Image

Mastering KVM Virtualization - Second Edition

By: Vedran Dakic, Humble Devassy Chirammal, Prasad Mukhedkar, Anil Vettathu

Overview of this book

Kernel-based Virtual Machine (KVM) enables you to virtualize your data center by transforming your Linux operating system into a powerful hypervisor that allows you to manage multiple operating systems with minimal fuss. With this book, you'll gain insights into configuring, troubleshooting, and fixing bugs in KVM virtualization and related software. This second edition of Mastering KVM Virtualization is updated to cover the latest developments in the core KVM components - libvirt and QEMU. Starting with the basics of Linux virtualization, you'll explore VM lifecycle management and migration techniques. You’ll then learn how to use SPICE and VNC protocols while creating VMs and discover best practices for using snapshots. As you progress, you'll integrate third-party tools with Ansible for automation and orchestration. You’ll also learn to scale out and monitor your environments, and will cover oVirt, OpenStack, Eucalyptus, AWS, and ELK stack. Throughout the book, you’ll find out more about tools such as Cloud-Init and Cloudbase-Init. Finally, you'll be taken through the performance tuning and troubleshooting guidelines for KVM-based virtual machines and a hypervisor. By the end of this book, you'll be well-versed with KVM virtualization and the tools and technologies needed to build and manage diverse virtualization environments.
Table of Contents (22 chapters)
1
Section 1: KVM Virtualization Basics
4
Section 2: libvirt and ovirt for Virtual Machine Management
11
Section 3: Automation, Customization, and Orchestration for KVM VMs
15
Section 4: Scalability, Monitoring, Performance Tuning, and Troubleshooting

Chapter 9: Customizing a Virtual Machine with cloud-init

Customizing a virtual machine often seems simple enough – clone it from a template; start; click a couple of Next buttons (or text tabs); create some users, passwords, and groups; configure network settings... That might work for a virtual machine or two. But what happens if we have to deploy two or three hundred virtual machines and configure them? All of a sudden, we're faced with a mammoth task – and it's a task that will be prone to errors if we do everything manually. We're wasting precious time while doing that instead of configuring them in a much more streamlined, automated fashion. That's where cloud-init comes in handy, as it can customize our virtual machines, install software on them, and it can do it on first and subsequent virtual machine boots. So, let's discuss cloud-init and how it can bring value to your large-scale configuration nightmares.

In this chapter, we will...