Case Study: The Value of Virtual I/O, New England Biolabs

When New England BioLabs realized that it had outgrown its 120 servers, it also soon discovered that options for physical expansion were limited and potentially costly--one option required the building of a tunnel. NEB provides enzymatic products for gene research and drug discovery and had housed its bioinformatics data center in an historic mansion. It was bursting at the seams; port utilization of its blade servers for networking and storage was at an unsustainable 99 percent. To address the problem, Thomas Peacock, IT architect at NEB, knew that the company's old 2U-per-server systems would have to go.

The decision was made to bring in two IBM Blade Center H Chassis, which delivered 14 servers in a 9U form factor, effectively increasing server density by a factor of six. Then came the question of how to provide connectivity. "We would have needed to purchase two IP switches and two SAN switches per Blade Center...[plus] various SAN and IP cards for each blade server," depending on the server's role and requirements, he said in an interview via e-mail. Managing all those discrete HBAs (host bus adapters) and NICs and would be a chore, particularly with today's bare-bones IT staff.

Another option was to virtualize I/O. Peacock knew that adding more virtual servers would only compound this I/O bottleneck. He was convinced that the solution lay in I/O virtualization, which extends the I/O bus from one or more servers to an external chassis, where it is more easily managed. Once he did the numbers, Peacock realized that he could save about $30,000 per chassis by purchasing an I/O virtualization solution--in this case Xsigo's I/O Director, which he had heard about at VMworld 2007. "The cost savings was possible by purchasing four Infiniband switches for the Blade Center H [chassis] rather than purchasing four Cisco switch modules and four Brocade switch modules," plus all the NICs and HBAs. Beyond the raw numbers, Peacock and his team have less to manage in terms of cards, switches and cabling, and fewer servers and racks. "This was a big plus for our team as we are already lean in staffing."

According to Jon Toor, vice president of marketing at Xsigo, I/O Director's main benefit is its ability to replace numerous cards with just one and to centrally manage them. "We take physical HBAs and NICs out," he said in a phone interview. "You'll see them as before from within an application, but now they're virtual." Cards can be moved and changed from one server to another based on workload or other reasons, he said, without touching the hardware. "[Admins] can add resources at any time without touching servers, and create new resources at the server level with simple software commands," he explains. Xsigo management software can stand alone or run as a tab inside VMware's Virtual Center control console. NEB virtualized the communications of its Fibre Channel SAN as well as all IP networking connectivity. "This enabled NEB to present multiple virtual NICs and virtual HBAs to VMware ESX hosts, which would otherwise be limited by the physical interfaces offered by the blade servers," Toor says. For NEB's operation, virtualizing I/O was key to its expansion: "We can handle 28 physical servers in our blade solution. If that was 28 2U servers, the power count would have been [for] 112 ports based on two NICs and two SAN ports for each server." With Xsigo, the total port count is 24 (20 GbE ports and four for the SAN). "We are significantly below what we were using before. We reduced our port utilization to 65 percent, we expect the number to fall to 43 percent, and we have plenty of room to grow."

Eight months into its five-year expansion plan, NEB is already ahead of schedule. "The server consolidation project was a component of a larger project to revamp the data center, [which] was ill sized by the team five years ago and had gone through reactionary changes without a roadmap," Toor said. With a roadmap that includes virtual I/O, VMware, blade servers and Infiniband firmly in place, NEB is on course to maximize savings in cost and efficiency.