Over the past few years virtualization, a method of running multiple computers on top of one host computer, has been steadily picking up in the enterprise as a way to ease costs and time of administration of company servers. Depending on the products that you use, whether it be VMware, Xenserver, Hyper-v or any other product the features vary.  Personally ever since the release of VMware ESXi into the free world I have been driven toward VMware products.

VMware’s ESXi Hypervisor gives you a host operating system with a small footprint of 32MB on disk.  Having this small of a footprint on the host side gives more resources and horsepower to the guest operating systems that are virtualized.  When you install ESXi on your server and once you get it configured for your network all the administration can be done through a console on a Microsoft Windows machine.

So enough with the technical marketing stuff, why should I go buy monster machines with tons of disk space just for virtualization?

- Security

If one of your virtual machines is compromised the rest of your virtual machines and the host are unaffected.  Once you install certain business critical applications onto separate virtual machines if one goes down the rest stay up.  You can consolidate your servers and keep downtime minimal.

- Performance

With virtualization you can assign virtual machines certain amounts of resources based on the total amount you have on the host machine.  This can let you prioritize certain resources based on the types of applications you use in the virtual machines.  This is also a good way to gauge the resource usage of your application.

- Consolidation

You can move several servers depending on their use to one machine and make it virtual.  They have products that will take your single server machine and turn it into a virtual machine file so you can move it (VMconverter).   Once you begin consolidating machines you can save on rack space and the amount of power you use.  In the future you will save on costs of hardware and hardware support because you will buy fewer servers.

- Maintenance and Downtime

Virtualization can make patching and updating a lot easier.  Once a month or so before you put on your operating system patches you can take a snapshot of the virtual machine file which contains all of your operating system and application data.  If disaster hits and patches or updates bring down your application you can revert back to your previous snapshot.  With having a snapshot before this upgrade you can decrease downtime significantly and have you application back up in no time.

There are many more benefits to virtualization that can lower costs of hardware and administration. If you wish to look into virtualization further you can visit the VMware website by going to: http://www.vmware.com or drop me a comment with questions.