There are three methods of virtualization available. Each has their benefits and should be considered when choosing if virtualization is right for you. It is important to understand the different virtualization options so you get the right solution. While they all can offer similar benefits of flexibility, redundancy, and availability, it can often depend on the way the infrastructure is built. Technology can only be as good as the people who manage and control it.

Software Virtualization (Virtuozzo Software)

Software Virtualization takes a single server and operating system and uses software to create virtual machines and allocates the available server resources on one underlying operating system.

Benefits:

• Offers a virtual environment to create a unique system configuration for a customized server
• Snap shot technology makes backups and restores very efficient
• Cloning features creates ideal development environments

Uses:

• Online website that requires custom software or server configurations
• Application that requires private environment
• Development environment

Need to Know:

• Shares resources and can often compete for available resources on the server
• Shares one underlying Operation System version

Full Virtualization: (VMWare Software)

Full virtualization takes hardware and uses software to emulate the servers. It uses a host machine which then manages the guest machines. It consists of a “host” machine (an actual hardware PC/server), and a “guest” machine (a virtual machine) which runs like any old application does on the “host” (yes, just like Outlook, or Word! Well, almost…). A virtual machine uses a combination of the host machine’s system resources to create a unique instance of the emulated platform on the host, operating independently as its own computer. Even the network assigns it its own connection!

Benefits:

• Ability to consolidate servers
• High availability service
• Mirrored resources that are allocated to the server are always available
• Built in load balances to ensure quality of service
• Fault tolerance available for single CPU servers to offer zero downtime
• Boot time is minimum based on technology
• Supports all software, does not require "virtual" version
• Software is not tied to or dependent on the hardware

Uses:

• Dedicated servers can be put into a virtual environment
• Applications, intranets, websites or nearly anything that is stored on a server and may talk to other servers

Need to Know:

• High I/O applications do not perform as well as on a physical server

Paravirtualization: (Xen Software)

Similar to the full virtualization, this service requires a modified operating system. Therefore, the guest machines have additional software on it. The virtualization software works with the operating system which can provide ideal performance for the High I/O applications and will work more like a physical machine. However, there can be challenges with the modified OS in some applications.