Book Image

KVM Virtualization Cookbook

By : Konstantin Ivanov
Book Image

KVM Virtualization Cookbook

By: Konstantin Ivanov

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
About the Author
About the Reviewer
Customer Feedback

Resource usage collection with libvirt

The first step in monitoring virtual machines is to get familiar with the tools to collect metrics on the subsystems we would like to later alert on. In this recipe, we are going to focus on CPU, memory, and block device utilization of the KVM guests. We are also going to learn how to use the QEMU monitoring socket and the QEMU guest agent.

Libvirt exposes a set of calls that the virsh command leverages to gather resource usage information on the specified guest/domain. We are going to monitor and alert on the information collected here in the Monitoring KVM instances with Sensu recipe later in this chapter.

Getting ready

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

  • A server with libvirt installed and configured
  • A running KVM instance

How to do it...

To collect various resource usage information for a running instance or the hypervisor host, perform the following:

  1. Obtain information on the hypervisor CPU utilization:
root@kvm:~# virsh nodecpustats -...