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

Introduction


With libvirt, we can define different network types for our KVM guests, using the already familiar XML definition syntax and the virsh and virt-install userspace tools. In this chapter, we are going to deploy three different network types, explore the network XML format, and see examples on how to define and manipulate virtual interfaces for the KVM instances.

To be able to connect the virtual machines to the host OS or to each other, we are going to use the Linux bridge and the Open vSwitch (OVS) daemons, userspace tools, and kernel modules. Both software bridging technologies are great at creating Software-defined Networking (SDN) of various complexity, in a consistent and easy-to-manipulate manner. The Linux bridge and OVS both act as a bridge/switch that the virtual interfaces of the KVM guests can connect to.

With all this in mind, let's start by learning more about the software bridges in Linux.