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
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Offline migration using the virsh command and local image


Performing offline migration with virsh does not require a shared storage; however, we are responsible for providing the guest filesystem to the new host (by coping the image file and so on). The offline migration transfers the instance definition without starting the guest on the destination host and without stopping it on the source host. In this recipe, we are going to perform an offline migration using the virsh command on a running KVM guest using an image file for its filesystem.

Getting ready

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

  • Two libvirt hosts and a running KVM instance. If one is not present on your host, you can install and start a new guest VM using a local image file:
root@kvm:~# virt-install --name kvm_no_sharedfs --ram 1024 --extra-args="text console=tty0 utf8 console=ttyS0,115200" --graphics vnc,listen=0.0.0.0 --hvm --location=http://ftp.us.debian.org/debian/dists/stable/main/installer-amd64/ -...