The birth of enterprise virtualization

November 10, 2003: A group of IT executives in dresses, business suits, and blazers stood around a boardroom, watching a screen projecting a video clip of Terminator II: Judgement Day. "Are you ready?" said one of the men standing at a podium. On the bottom right of the screen, a small box of a few Microsoft Windows control panels displayed icons representing running servers.

These servers were virtual machines, and the video clip the room was watching was being played from a file server on one of these virtual machines. Suddenly, the host clicked on a few context menus on the virtual machine and a progress bar appeared. The video continued to play as the T-1000 Advanced Prototype morphed from liquid metal into human form, chasing John Connor in a burning police car. The room exploded with hoots, hollers, and cheers—and it wasn't because of the Terminator. This was a demo of a technology called VMotion, which would revolutionize the IT operations world for years to come.

Although virtualization had been around out since the 1960s, VMware can certainly be credited for bringing it to the masses in their official release of VMware VirtualCenter featuring VMotion. VMotion allowed system engineers to convert their existing physical machines to hypervisors, enabling the running of virtual machines. It also kept those virtual machines up by live-migrating them to another hypervisor in the event of an underlying hardware problem. This was done by transferring the virtual machine's active memory and execution state over the network.

Software developers and system engineers alike were overjoyed with the technology, knowing they would now sleep quite well while their application hummed along regardless of hardware headaches. The software developers continued to develop their incredible applications, but their development methodology remained the same. They were still developing their application as if they were on traditional physical machines!

Gartner, the information technology research and advisor company, has labeled this type of environment Mode 1, otherwise known as enterprise virtualization. In fact, enterprise virtualization still exists today and is the most adopted type of the cloud by enterprises around the world. See Figure 1.1.

Here are some common characteristics of the enterprise virtualization cloud:

• GUI-emphasized: When one creates a new virtual machine in this model, they typically do so via a Graphical User Interface (GUI). This may be something like vSphere Web Client or Hyper-V Manager. Command-line tools may exist but are less popular with a majority of its operators.
• Expensive hardware: Enterprises that buy into enterprise cloud also buy into expensive blade servers, SANs, network/fabric switches, component redundancy, and high-cost, boutique super microcomputers—specialized hardware with a high price tag.
• Vertical scaling: If your application begins getting more traffic, the ability to scale will be necessary. In the enterprise virtualization world, this means assigning more resources to virtual machines powering the application. When one scales up or vertically, they go about this by adding more CPU, RAM, or disk space to the individual virtual machines. This is the opposite philosophy to scaling horizontally.
• Proprietary: The infrastructure code in this model is closed source. This includes software such as VMware VCenter powered by Microsoft Windows Server. If a bug is discovered while working with the software, it must be filed with the vendor. Because one monolithic organization controls access to the code, bug fixes can take weeks or months to be patched.
• Traditional software development: In an Enterprise Virtualization cloud, the software developer continues to develop the applications in the same manner they developed applications on physical machines. This is sometimes referred to as the monolithic approach. Although the web server or database may reside on different virtual machines, the application's functions are combined into a single program from a single platform. This differs drastically from the cloudy development approach explained in the next section.