Book Image

Mastering KVM Virtualization

Book Image

Mastering KVM Virtualization

Overview of this book

A robust datacenter is essential for any organization – but you don’t want to waste resources. With KVM you can virtualize your datacenter, transforming a Linux operating system into a powerful hypervisor that allows you to manage multiple OS with minimal fuss. This book doesn’t just show you how to virtualize with KVM – it shows you how to do it well. Written to make you an expert on KVM, you’ll learn to manage the three essential pillars of scalability, performance and security – as well as some useful integrations with cloud services such as OpenStack. From the fundamentals of setting up a standalone KVM virtualization platform, and the best tools to harness it effectively, including virt-manager, and kimchi-project, everything you do is built around making KVM work for you in the real-world, helping you to interact and customize it as you need it. With further guidance on performance optimization for Microsoft Windows and RHEL virtual machines, as well as proven strategies for backup and disaster recovery, you’ll can be confident that your virtualized data center is working for your organization – not hampering it. Finally, the book will empower you to unlock the full potential of cloud through KVM. Migrating your physical machines to the cloud can be challenging, but once you’ve mastered KVM, it’s a little easie.
Table of Contents (22 chapters)
Mastering KVM Virtualization
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Snapshots


A VM snapshot is a file-based representation of the system state at a particular point in time. The snapshot includes configuration and disk data. With a snapshot, you can revert a VM to a point in time, which means by taking a snapshot of a virtual machine you preserve its state and can easily revert to it in the future if needed. Snapshots have many use cases, such as saving a VM's state before a potentially destructive operation.

For example, suppose you want to make some changes on your existing web server virtual machine, which is running fine at the moment, but you are not certain if the changes you are planning to make are going to work or break something. In that case you can take a snapshot of the virtual machine before doing the intended configuration changes and if something goes wrong, you can easily revert to the previous working state of the virtual machine by restoring the snapshot.

libvirt supports taking live snapshots. You can take a snapshot of a virtual machine...