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

Editing snapshots


In this recipe, we are going to edit the XML definition of an existing snapshot and examine the changes.

Getting ready

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

  • A libvirt host with the QEMU toolset
  • The snapshots we created in the Creating snapshots recipe

How to do it...

To edit a snapshot, run the following:

  1. List all available snapshots for the specified KVM instance:
root@kvm:~# virsh snapshot-list kvm1
 Name                Creation Time              State
------------------------------------------------------------
 1492797458          2017-04-21 17:57:38 +0000  running
 kvm1_ext_snapshot   2017-04-21 18:08:49 +0000  disk-snapshot

root@kvm:~#


  1. Edit the disk snapshot and change its name and description:
root@kvm:~# virsh snapshot-edit kvm1 --snapshotname kvm1_ext_snapshot --rename
<domainsnapshot>
 <name>kvm1_ext_snapshot_renamed</name>
 <description>Disk only external snapshot for kvm1</description>
 ...
root@kvm:~#
  1. List the snapshots...