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


The libvirt library exposes a virtualization agnostic interface for controlling the full lifecycle of KVM (and other technologies, such as XEN and LXC) instances. Using the Python bindings we can define, start, destroy, and delete virtual guests, along with anything else the virsh userspace tool implements. In fact, we can see that the virsh command uses various libvirt shared libraries, by running:

root@kvm:~# ldd /usr/bin/virsh | grep libvirt
libvirt-lxc.so.0 => /usr/lib/x86_64-linux-gnu/libvirt-lxc.so.0 (0x00007fd050d88000)
libvirt-qemu.so.0 => /usr/lib/x86_64-linux-gnu/libvirt-qemu.so.0 (0x00007fd050b84000)
libvirt.so.0 => /usr/lib/x86_64-linux-gnu/libvirt.so.0 (0x00007fd050394000)
root@kvm:~#

The Python libvirt module, also provides methods to monitor and report the use of CPU, memory, storage, and network resources on the hypervisor node and other capabilities depending on the type of hypervisor driver in use.

In this chapter, we are going to use a small subset of...