Arthur Cole spoke with David Tareen, worldwide marketing manager, IBM Systems and Technology Group.
Cole: Now that IBM is bundling QLogic's 8 Gbps Fibre Channel cards in its blades, do you see the technology more as a tool to increase overall bandwidth, to consolidate more blades in a chassis, or both?
Tareen: It will depend on what type of IT project the client is engaged in. For clients who are deploying or upgrading their database and/or e-mail workloads, they will see this technology as a way to deliver the increased bandwidth these applications now need. For clients who are virtualizing and consolidating, they will see this as a larger pipe to drive more data traffic to their SAN. The client benefits are enormous here. 8 Gb sounds as if it offers double the throughput from the older 4 Gb. However, in our lab tests we have been able to prove that in environments where bandwidth is constrained, clients can support the same number of Exchange users by deploying 68 percent less switching and adapter hardware in the chassis. This benefit only comes out if clients use both switch and adapter running at 8 Gb.
Cole: Does it make sense to be pushing an 8 Gb blade chassis at this point? Wouldn't it make more sense to wait until there is a large installed base of 8 Gb FC SANs first?
Tareen: Great question. Yes it does (make more sense) because of two reasons. First, we have seen clients make their data center investments incrementally, especially investments across servers and storage. There are often different departments that manage their own project schedules, budgets, etc. Because IBM BladeCenter 8 Gb technology is compatible with 4 Gb, the chassis can be ready when the storage gets upgraded to 8 Gb as well.
The second reason is that storage networks do not always perform as straight input and output streams. A single server request can go to multiple storage devices. In this architecture, the bottleneck is often the HBA and switch, while the disk controller can manage the bottleneck by using additional disks or using the right RAID structure. Hence, a faster HBA and switch architecture will incrementally benefit a client.
Cole: Some would argue that the future for Fibre Channel hardware is limited because it will be cheaper and more effective to run FC as an Ethernet layer under the new FCoE standard. Do you agree?
Tareen: That may eventually happen. However, the sheer volume of existing Fibre Channel hardware and ports in the data center, combined with the years of Fibre Channel skill will drive the client investment for some time. We will see the next iteration of Fibre Channel speeds before the industry goes completely to FCoE. But I would say on the last point that the jury is still out on FCoE. While customers like the concept of a unified fabric, it is yet unproven, and like all new technologies, it will take time for it to mature and reach wide adoption levels.