Server Virtualization: Manage the Load
Server virtualization has begun taking center stage at online colleges, where investment in IT infrastructure has proven essential to a school's ability to serve its student body solely over the web.
For instance, at Charter Oak State College in Connecticut, a public online college that serves more than 2,000 students, CIO George F. Claffey had a vexing challenge about 18 months ago.
In 2007 and 2008, the state of Connecticut, which normally funds servers and other IT equipment through a dedicated capital fund, approved but did not release funds to Charter Oak for its infrastructure. Thus, in the span of 20 months, the college found itself with a shortfall of almost $1 million in IT funding – at the same time that demand for its program was growing at roughly 20 percent a year.
For several years, Claffey managed student and course demand by adding new physical servers, one at a time. The problem was that the new servers took several weeks to purchase, provision and deploy, and the result was multiple servers with multiple configurations, many of which went underutilized.
Photo credit: Amy Etra
In the online world, waiting several weeks for a new server to be provisioned is not feasible, so the solution was to virtualize the school's servers and standardize on server, storage and switching hardware.
“We needed to buy a base of capacity and provision virtual machines on the fly as course demand developed,” explains Claffey, who says that now he and his staff can add systems resources such as disk space and memory fairly easily using VMware.
Stretching the Benefits
In addition to working for Charter Oak, Claffey serves as CIO for the Connecticut Distance Learning Consortium. Created in 1998, CTDLC offers customized, turnkey solutions that range from online learning system hosting and integration services to instructional design, electronic tutoring and technical support. Today, the consortium supports 80,000 students in online programs at 43 schools and colleges.
CTDLC went virtual in tandem with Charter Oak, but on a much larger scale.
“For CTDLC, we went down from about seven racks and 50 servers to about two racks and 10 servers,” says Claffey. “While the physical server to virtual deployment has advantages, the real benefit is the ability to test, create, modify and maintain multiple â€˜clones' to provide test, development and patch environments with as little as a click of the VM console.”
Virtualization has more than paid for itself, says Claffey, who points out that Charter Oak “served more students this year than it did last year, while reducing its overall technology budget by 20 percent.''
Kenneth C. Green, director of the Campus Computing Project, says there's no question that virtualization offers big gains in capacity and cost containment.
“Although the benefits of virtualization are not limited to distance education,” says Green, “online learning has become a new driver because much of the content is data intensive media such as voice and video images that require a more efficient way to handle all the resources.”
Lower Costs, More Efficiency
Another college that is using server virtualization to save money and add IT management efficiencies is the online education division at Bryant & Stratton College in Orchard Park, N.Y. The college has been hosting online classes since 1999 and today serves more than 1,000 students, primarily in New York, Ohio, Virginia and Wisconsin.
Jonathan Blair, the school's director of Internet architecture, says rather than take the more standard VMware route, Bryant & Stratton deployed Virtuozzo from Parallels. The advantage, says Blair, is that he can fit more virtual machines per server, and more important, he can run Virtuozzo on the school's existing servers. Blair now has four servers running Virtuozzo and two that he has converted for SAN data storage.
By using existing servers, Blair says, the deployment cost well under $50,000, roughly half of the cost of a VMware ESX server and a SAN appliance.
“This system was extremely cost efficient. Plus, as we have grown, it allows us to apply resources more flexibly,” says Blair. “It has many of the management features VMware offers. For example, I can manage CPU utilization and memory, and can also do traffic shaping and widen the pipe for the most active applications.”
Tips for Going Virtual
- Be selective in what you virtualize. Not every server is a good candidate for virtualization. Web and application servers tend to be good candidates, while processing-intensive transaction databases are more difficult to virtualize.
- Understand that security is still a major issue. People tend to think that because an organization is consolidating servers, it is decreasing its security risks. On the contrary, IT shops have to actively manage security, more than likely with existing network management tools.
- Plan for additional management overhead. The best virtualization environments are integrated with storage area networks. But that means the IT staff has to be trained on the SAN, as well as trained on the virtualization software, whether it's VMware, Microsoft's Hyper-V or Virtuozzo from Parallels.
- Rethink disaster recovery. Virtualization lets the IT staff more easily take snapshots of the virtual machines and then load them on servers that reside at a disaster site. One good rule of thumb is to budget roughly 25 percent of your virtualization project for disaster recovery.
- Plan for more complicated licensing agreements. Each vendor will have a different policy about how they handle virtualized licenses. Some will license per host, per virtualized machine, per processor core or per thread. Migrating to a virtualized environment requires discussion with each provider about how they approach licensing.