Book Image

KVM Virtualization Cookbook

Book Image

KVM Virtualization Cookbook

Overview of this book

Virtualization technologies such as KVM allow for better control over the available server resources, by deploying multiple virtual instances on the same physical host, or clusters of compute resources. With KVM it is possible to run various workloads in isolation with the hypervisor layer providing better tenant isolation and higher degree of security. This book will provide a deep dive into deploying KVM virtual machines using qemu and libvirt and will demonstrate practical examples on how to run, scale, monitor, migrate and backup such instances. You will also discover real production ready recipes on deploying KVM instances with OpenStack and how to programatically manage the life cycle of KVM virtual machines using Python. You will learn numerous tips and techniques which will help you deploy & plan the KVM infrastructure. Next, you will be introduced to the working of libvirt libraries and the iPython development environment. Finally, you will be able to tune your Linux kernel for high throughput and better performance. By the end of this book, you will gain all the knowledge needed to be an expert in working with the KVM virtualization infrastructure.
Table of Contents (15 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Defining KVM instances


In this recipe, we are going to define a virtual instance by creating a simple XML configuration file that libvirt can use to build the virtual machine. We are going to describe some of the XML schema blocks and look at examples of how to generate the XML definition file using the virt-install command rather than writing it manually.

Getting ready

For this recipe, we are going to need the following:

  • The QEMU binaries, provided after following the Installing and configuring QEMU recipe from Chapter 1, Getting Started with QEMU and KVM.
  • The custom raw Debian image we built in the Installing a custom OS on the image with debootstrap recipe from the previous chapter.

Note

You can use your own virtual machine image or download one from the Internet, as we showed in the Using pre-existing images recipe in Chapter 1, Getting Started with QEMU and KVM.

How to do it...

To define a new KVM virtual machine, run the commands outlined here:

  1. List all virtual machines on the host OS:
root...