Virtual Machines… Are They Real?

   Yes, virtual machines are real and they can provide your business with some real advantages.

   Let’s start with a physical computer. A typical small business may have three or four servers and 20 to 30 pc’s. These are physical boxes with an operating system, say Windows Server 2003 or Windows XP. In the physical world, there is only one operating system loaded on each box.

   Many years ago, Citrix and Microsoft pioneered the ability to present users with their own set of application icons or even a desktop using just one server. This was an early form of virtualization.

   Fast forward to the present and what you find is the ability to have one or more complete virtual computers running simultaneously on just one physical computer! By ‘complete’ we mean it boots up like a pc, it has its own operating system, it has its own user security, etc. It simply displays in its own window on the host computer’s desktop.

   There are some distinct advantages to employing the use of virtual machines. A virtual machines (VM) is stored in one big file. This means that you can backup a VM and more importantly restore a VM just as easily. It often takes close to a day to restore a physical server depending on the quality of the backup. With a VM, it takes a fraction of that time.

   Here are just a few examples of how VM’s can be used. 1) You are testing out some new software and don’t want to interrupt users on a production server because of reboots and tricky integrations. A virtual machine runs in a ‘sand-box’ which is completely isolated from everything else. 2) Downtime for one or two days is not acceptable if one of your servers crashes. VM’s are used as part of the overall disaster recovery plan. P2V - physical to virtual – is the process of turning a physical computer (server or workstation) into a virtual one. Should the real server crash, being able to bring it back up quickly in a virtual machine will keep people working. While you wait for parts for the real server, employees can connect to the VM. Any work done on the VM can be saved and move back over to the physical server once it is up and running again. 3) You want to make better usage of your hardware expenditures and consolidate several existing servers onto one physical computer. In one recent Beachwood engagement, the client was able to shut down four old computers and put them all on one new server with one VM. 4) You have Windows Vista on your notebook pc but need to run an application that is only compatible with Windows XP. You can set up a VM on a desktop or notebook pc just like you can on a true server computer.
Virtual Machines are not perfect and do require substantial resources on the Host machine which is the physical computer and native operating system. On one server we deployed recently, we configured it with 12 GB of high speed RAM along with fast SAS drives.

   Microsoft’s new Server 2008 operating system has a feature called Hyper-V that controls the use of virtual machines. Citrix and VMware have excellent offerings as well. When you purchase Microsoft Server Standard Edition you are licensed to use that same operating system in one VM. With the Enterprise Edition, you are licensed for four VM’s. In effect, you can now have 2 or 5 servers for the price of one.