SUSE Linux Enterprise Server includes the latest open source virtualization technologies, Xen and KVM. With these hypervisors, SUSE Linux Enterprise Server can be used to provision, de-provision, install, monitor and manage multiple virtual machines (VM Guests) on a single physical system.
SUSE Linux Enterprise is an enterprise-class Linux server operating system that offers two types of hypervisors: Xen and KVM
Both Xen and KVM support full virtualization mode. In addition, Xen supports paravirtualized mode. In Xen, the management components run in a privileged VM Guest often called Dom0.
Virtualization BenefitsLess hardware: You can run several operating systems on one host, so all hardware maintenance will be reduced.
Less power/cooling: Less hardware means you do not need to invest more in electric power, backup power, and cooling if you need more service.
Save space: Your data center space will be saved because you do not need more hardware servers (fewer servers than service running).
Less management: Using a VM Guest simplifies the administration of your infrastructure.
Agility and productivity: Virtualization provides migration capabilities, live migration and snapshots. These features reduce downtime and bring an easy way to move your service from one place to another without any service interruption.
Components of a Xen-based virtualization environment
Xen hypervisor, Dom0, any number of other VM Guests, and the tools, commands, and configuration files that let you manage virtualization. Collectively, the physical computer running all these components is called a VM Host Server because together these components form a platform for hosting virtual machines.Xen Hypervisor
The Xen hypervisor, sometimes simply called a virtual machine monitor, is an open source software program that coordinates the low-level interaction between virtual machines and physical hardware.Dom0
The virtual machine host environment, also called Dom0 or controlling domain, is composed of several components, such as:
- SUSE Linux Enterprise Server provides a graphical and a command line environment to manage the virtual machine host components and its virtual machines.
- The xl tool stack based on the xenlight library (libxl). Use it to manage Xen guest domains.
- QEMU—an open source software that emulates a full computer system, including a processor and various peripherals. It provides the ability to host operating systems in both full virtualization or paravirtualization mode.
A Xen-based virtual machine, also called a VM Guest or DomU, consists of the following components:
- At least one virtual disk that contains a bootable operating system. The virtual disk can be based on a file, partition, volume, or other type of block device.
- A configuration file for each guest domain. It is a text file following the syntax described in the manual page man 5 xl.conf.
- Several network devices, connected to the virtual network provided by the controlling domain.
There is a combination of GUI tools, commands, and configuration files to help you manage and customize your virtualization environment.
Xen Virtualization Architecture