This book covers Xen—an open-source paravirtualization technology that provides a platform for running multiple operating systems on one physical hardware resource, while providing close to native performance. Xen supports several operating systems—Linux, FreeBSD, Windows, and NetBSD. It was originally developed in 2003 at the University of Cambridge Computer Laboratory and now both commercial and free versions of the Xen hypervisor are available. The commercial versions are built on top of the open-source version and have additional enterprise features. In this book we explore and use the open-source version of Xen.
Each chapter in this book is a collection of practical tasks that demonstrates how to achieve common virtualization tasks—you then learn how it works so that you can apply this knowledge to your Xen installation and environment.
Chapter 1 introduces the world of Xen and virtualization. It discusses the concepts and advantages of using Xen.
Chapter 2 walks us through the installation of Xen on a Fedora Core system. It discusses installation using yum and also installation by compiling from source.
Chapter 3 creates virtual machines or Xen guest domains that run on top of our Fedora Core system. Ubuntu Feisty, NetBSD, CentOS, and Slackware domains are created.
Chapter 4 explores the management tools available for administering Xen instances. It shows how to install and use xm, XenMan, and virt-manager.
Chapter 5 examines some of the networking options that are available when using Xen and walks through both bridged and routed networking configurations for connecting guest domains to each other as well as to the outside world.
Chapter 6 walks us through some of the storage options that can be used for storing Xen domains. Storage systems such as the file system, Network File System (NFS), and Logical Volume Management (LVM) are discussed.
Chapter 7 shows how to secure Xen domains by encrypting the root file systems. The two techniques covered are plain device mapper-based encryption and key-based encryption using LUKS.
Chapter 8 introduces the options available for the migration of Xen instances. We will save and restore domains, and explore live migration. We will also look at what happens behind the scenes when Xen performs a live migration of a domain.
Chapter 9 talks about some of the newer ideas based on Xen such as libvirt—a virtualization API for interacting with multiple virtualization implementations, and VMCasting—an RSS based technology that can automate the deployment of Xen images using the RSS 2.0 format.
Chapter 1 introduces the world of Xen and virtualization. It discusses the concepts and advantages of using Xen.
Chapter 2 walks us through the installation of Xen on a Fedora Core system. It discusses installation using yum and also installation by compiling from source.
Chapter 3 creates virtual machines or Xen guest domains that run on top of our Fedora Core system. Ubuntu Feisty, NetBSD, CentOS, and Slackware domains are created.
Chapter 4 explores the management tools available for administering Xen instances. It shows how to install and use xm, XenMan, and virt-manager.
Chapter 5 examines some of the networking options that are available when using Xen and walks through both bridged and routed networking configurations for connecting guest domains to each other as well as to the outside world.
Chapter 6 walks us through some of the storage options that can be used for storing Xen domains. Storage systems such as the file system, Network File System (NFS), and Logical Volume Management (LVM) are discussed.
Chapter 7 shows how to secure Xen domains by encrypting the root file systems. The two techniques covered are plain device mapper-based encryption and key-based encryption using LUKS.
Chapter 8 introduces the options available for the migration of Xen instances. We will save and restore domains, and explore live migration. We will also look at what happens behind the scenes when Xen performs a live migration of a domain.
Chapter 9 talks about some of the newer ideas based on Xen such as libvirt—a virtualization API for interacting with multiple virtualization implementations, and VMCasting—an RSS based technology that can automate the deployment of Xen images using the RSS 2.0 format.
In this book, you will find a number of styles of text that distinguish between different kinds of information. Here are some examples of these styles, and an explanation of their meaning.
There are three styles for code. Code words in text are shown as follows: "Create a directory named xen-images. We will create all our guest images in this directory."
A block of code will be set as follows:
<?xml version="1.0" ?><appliance> <name xml:lang="en">
Any command-line input and output is written as follows:
~ make linux-2.6-xenU-config
New terms and important words are introduced in a bold-type font. Words that you see on the screen, in menus or dialog boxes for example, appear in our text like this: "clicking the Next button moves you to the next screen".
Note
Tips and tricks appear like this.
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