Book Image

Getting Started with oVirt 3.3

By : Alexey Lesovsky
Book Image

Getting Started with oVirt 3.3

By: Alexey Lesovsky

Overview of this book

<p>Virtualization technologies are evolving very rapidly. With advanced capabilities for hosts and guests including high availability, live migration, storage management, system scheduler, and many more, oVirt comes with the latest advancements in the field of open source virtualization. oVirt is built on the powerful Kernel-based Virtual Machine (KVM) hypervisor and on the RHEV-M management server, and it allows you to utilize the most advanced capabilities of virtualization in an easy and efficient way.</p> <p>Getting Started with oVirt 3.3 talks you through the internal structure and working of oVirt 3.3 using a practical, hands-on approach. You will learn how to install and set up your own virtualization infrastructure as well as in what order you should configure your virtualization environment, what features oVirt has, and how to use them. You will also learn how easy it is to create cluster policies to control the operation of a cluster as well as how to create and use a virtual machine template.</p> <p>With this book, you will learn how to run your own data centers in different configurations and about the existing opportunities for creating virtual machines. You will perform the re-balancing of clusters and quickly create dozens of virtual machines. This book will also help you create a network environment and set policies for QoS. You will also learn how to manage users and allocate resources between them. Getting Started with oVirt 3.3 teaches you everything you need to know about oVirt 3.3 and shows you how to get the most out of the technology quickly and effectively.</p>
Table of Contents (15 chapters)

Snapshots


Snapshot is a special way to catch the virtual machine state. This feature is very useful when you need to fix the state prior to any change in the system, or vice versa after reaching a certain state. For example, this may be the software installation or a large-scale configuration update that affects a large number of system packages and files. The reasons may be very different. Creating a snapshot implies a checkpoint where the state of the filesystem is fixed. In addition to creating images for block devices, you can create a snapshot of memory.

In fact, a snapshot is a single file or block device. For storage with file access (such as NFS or Gluster), snapshot is a separate file. For storages with block access (such as iSCSI or FC) snapshot is a separate LVM volume, which is located at the LVM physical volume (oVirt virtualization hosts use the attached storage as LVM). However, snapshots cause decrease in the VM's performance. When a snapshot is created, the original disk...