6 tips for server virtualization

Despite the years of buzz about the benefits of server virtualization, most agencies have only virtualized a small portion of their servers — or none at all. Only about 10 percent of today’s physical servers are virtualized, but within three years, that number could grow to 60 percent, said Philip Dawson, a research vice president at Gartner. The reason for his bullish outlook is that virtualization allows administrators to run multiple applications and operating systems on a single server, which helps agencies reduce costs and increase efficiency. But as virtualization continues to be a growing force in data centers, chief information officers need the right strategies to successfully reconfigure their servers and prepare for the ripple effects on related technology infrastructure, such as storage and networks. Public-sector CIOs, analysts and government contractors offer six tips for getting the most out of virtualization.Rather than being a one-size-fits-all solution, server virtualization must address the unique goals and resources of each agency that implements the strategy.The primary goal of a virtualization project might be reducing the number of physical servers, improving hardware use, cutting power consumption, bolstering disaster recovery capabilities or a combination of those objectives. Information technology managers must clearly define a practical endpoint and strategy based on the agency’s existing resources and any restrictions imposed by budget and staff expertise. Solicit input from a wide cross-section of staff members during the planning stages. As part of its virtualization deployment, the Treasury Department’s Office of the Comptroller of the Currency formed a 15-member implementation team with experts in application development, security, IT infrastructure management and business operations. They helped formulate a plan for reducing the number of servers and improving performance. The agency then used a test-and-development environment to build a prototype. “We focused on both functional and performance testing before any changes were introduced” to production systems, said Bajinder Paul, the office’s CIO. “Even after exhaustive testing and documentation, we introduced changes in the production environment incrementally, not in one quantum leap. You want to be able to manage your risks in a stepwise, incremental fashion.”Established techniques for determining the right amount of server horsepower might not work in a virtualized data center. Avoid falling into the trap of the two configuration extremes: Underpowered virtual servers fail to meet an organization’s processing needs, and over-engineered systems waste money on unnecessary resources, thereby diluting potential cost savings.  Typically, servers built on standard quad-core, four-processor chipsets can easily power virtual servers that run a dozen or more applications. When IT officials in Gaston County, N.C., turned to virtualization to reduce IT costs and improve disaster recovery times, they chose quad-core devices with 32G of RAM for most of their needs. Early on, CIO Brandon Jackson said he was tempted to buy more expensive devices. Managers “automatically assume they’ll need the biggest, baddest box” to run multiple applications, he said. “But my staff told me they could run between 12 and 20 servers on one piece of hardware, and that’s the way it has turned out.” Many IT managers don’t realize how underused their servers are when they’re supporting a single operating system and set of applications, he a dded. Virtualization doesn’t work for all applications. To determine which programs are right for virtualization, experts suggest identifying their relative importance to the organization, their processing requirements and staff members expertise in managing them. And making those determinations can “take longer than the vendors suggest,” Dawson said.   Think twice about virtualizing applications with intensive input/output demands, such as high-end databases and mail servers. With that in mind, IT officials in the Fulton County, Ga., government decided to keep their telephony applications on dedicated physical servers, said Ryan Fernandes, the county’s CIO and IT director.Good virtualization candidates include applications that require the least maintenance and draw relatively low amounts of server CPU and memory resources, said Tom Simmons, area vice president at Citrix Federal. There are now more choices for virtualization software, with Citrix Systems, Microsoft, Virtual Iron and others making inroads on market leader VMware. Before entering into long-term commitments, IT managers should consider which vendors offer the best deals and technology features. Each platform has different capabilities, with some offering high-availability features and others promoting ease of management, analysts and contractors say. Established vendors usually offer the benefits of a long track record and comprehensive compatibility testing to ease the task of matching virtualization technology with the devices in an agency’s infrastructure, said Aris Ventura, a storage specialist at CDW. But agencies that look beyond those benchmarks could get better licensing deals from companies looking to grow in the market, he added. Centralized, pooled storage is essential for high availability and the ability to dynamically allocate virtual-server resources. That storage pool can be delivered using Internet SCSI-based network-attached storage or Fibre Channel-powered storage-area network (SAN) appliances.When data resides on hard drives in physical servers, hardware failures can bring down virtualized applications even when the agency designates a second virtual server as a backup. “The secondary box has no way of knowing where to pull the data from,” Ventura said. “But with centralized storage, there is still access to the data” from functioning servers. Although central storage systems are important for virtual-server efficiency, CIOs and analysts say agencies should avoid tackling changes to servers and storage simultaneously. “Don’t try to virtualize storage as part of the server solution because that will be too complicated,” Dawson said. “Do storage beforehand as a foundation” for consolidating servers. For many organizations, improved disaster recovery is a prime reason they are attracted to virtualization. But some agencies find their virtualization platform doesn’t meet all their needs, so they supplement their continuity-of-operations portfolio with third-party technology for automatic failover and data replication. Evaluate server platforms and third-party technologies for tools that can automatically redirect traffic to a backup virtualized server. Gaston County officials deployed two SANs — one to hold production data and another to store information at a disaster recovery site. Technology from Compellent regularly duplicates data to the backup site to keep it current. "At any point in time, we’re no more than 15 minutes behind our production system,” Jackson said.Similarly, Fulton County uses Symantec’s LiveState to automatically create snapshots of data and configurations so backup servers can maintain up-to-date copies of production systems. That capability proved valuable when the county’s tax system failed after the virtualized environment was implemented. Although taxpayers might have been disappointed, the county recovered the virtual environment within hours rather than the day or more that would have been required in the past, said Keith Dickie, assistant director in the county’s Infrastructure Group. “That’s revenue the county uses to operate with so we can’t afford to be down,” he said.