If you have attended the last few AICPA Tech+ conferences you will not be surprised when I tell you who was the speaker in this year’s Virtualization Session: Randy Johnston

Randy Johnston is a top rated speaker and has more than 30 years of technology experience. He is also a published author of 5 books and leads a successful technology and business consulting firm – NMGI (Network Management Group Inc.)

Randy described the “Virtualization” as technology that enables one physical workstation or server to run multiple operating systems and related applications at the same time.

What is a virtual machine? The short answer is: “Software machines within hardware machines”

Here are is some key terminology before we dig deeper into Randy’s session:

–          Virtualization: A broad term that refers to the abstraction of computer resources. A disk file is created that has a complete OS and applications, and several of these can be run on the same machine at the same time.

–          Hypervisor: A virtual machine operating system

–          Host O/S: When not using hypervisor, this refers to the operating system, such as Windows Vista, XP, 7 or Linux, running on the host workstation or server.

–          Guest O/S: Refers to the operating system, such as Windows XP, loaded in the Virtual Machine

–          Hardware Support: Advanced hardware functionality to support VMs that is being built-in to new processors

When to use “Virtualization”:

–          On desktops to overcome incompatibilities between an O/S and legacy applications or hardware

–          On servers to reduce the number of physical servers to improve utilization, performance and reliability while reducing IT costs

–          For storage to consolidate server disks for better performance, easier backup, and greater reliability

–          To package applications with an O/S and all utilities to make them easier to install, deploy and update

The key Virtualization players / vendors:

–          Microsoft: Virtual Server 2005, Hyper-V, Virtual PC, Windows 7 in XP Mode

–          VMware: ESX server, Desktop workstation for all major O/S

–          Linux XEN

Desktop Virtualization & Advantages:

–          You can run multiple desktop OS platforms and related applications to overcome incompatibilities

–          You can demonstrate or test software without danger of contaminating the host system

–          You can save stable versions of desktop environments and distribute to other users

–          You can use it as means of protection from viruses, Trojans, and other malware

–          You can do all that but have to be careful with licensing the VMs. You must have a license for all software or OS on the VM just as any other computer

VMware Workstation vs Virtual PC:

So you are ready to experiment or deploy VMs in your environment, but which software vendor to chose? According to Randy Johnston and his experience with VMs and Hypervisors, you would probably be OK with Microsoft’s Virtual PC, but if you want more functionalities and performance then you will need to obtain VMware’s product (VMware Workstation 7). Workstation 7 offers support for Linux, NetWare, Windows OS, it uses smaller virtual disks, it has 64-bit application support, better printer support, and VMs can be easily migrated to server.

Portable Virtual Machines:

If mobility is important for you, then you should look into VMware Ace or Pocket Ace products. With those you can convert a virtual PC into a standard desktop package, deploy it to clients and manage it with Ace Management Server. You can also take your virtual computer on your iPod or USB flash drive while everything remains encrypted and secure.

Hardware & Software Considerations:

When virtualizing server environment you should be really careful when selecting hardware and software. If possible, you should use advanced CPUs (processors) like the Intel Xeon 5500 Quad Core and AMD Opteron Quad Core. Use, when possible, 64bit operating systems as they will support more RAM. Always consider virtualization based on storage arrays (SAN). It will give you better performance, flexibility, and it will provide with more DR and backup options such as replication and load balancing.


Virtualization is a great technology that gives us so much more options and flexibility as our technology changes our firms. We can run our companies more efficiently with fewer physical servers; have greater hardware utilization, and greater reliability & disaster recovery that actually cost us less money in the long term! Nothing is stopping you from experimenting! ESXi is a free download that will get you up and running in less than 30 minutes!!!