IBM boasts of full 8Gb Fibre Channel for blades

IBM is making the rounds this week talking up a new 8 Gb Fibre Channel daughter cards for its BladeCenter blade servers, saying that it is the only blade maker that can deliver 8 Gb performance all the way out to the storage area network.

The company this week will begin reselling a new 8 GB/sec Fibre Channel daughter card for blades made by QLogic. IBM has been selling a different QLogic adapter, which puts two 4 Gb Fibre Channel ports and a Gigabit Ethernet port on the same card, for the past several months, but the new QLogic card and the inherent bandwidth in the backplane of the BladeCenter H and HT chassis is allowing IBM actually get 8 Gb FC performance end-to-end.

Alex Yost, the vice president in charge of BladeCenter products at IBM, contends that while competitors in the space - notably, Hewlett-Packard, which has dominant market share at this point in the blade server space - have 8 Gb FC adapters and switches, none of them can deliver end-to-end performance because of bandwidth bottlenecks in their chasses.

Yost says that in performance tests IBM has run in its labs, the BladeCenter H chassis has been able to deliver an aggregate 40 GB/sec of bandwidth. (That's gigabytes, not gigabits.)

"So 8 Gb Fibre Channel and 10 Gigabit Ethernet are well within the capability of the existing backplane," Yost says.

Blade servers have a limited amount of I/O expansion, so addressing all of the possible networking needs of customers means having a variety of adapters, switches, and passthrough modules. IBM currently sells Fibre Channel switch modules for the BladeCenters made by Cisco Systems, Brocade, and QLogic, as well as FC adapters for the blades from QLogic and Emulex.

On the Ethernet front, IBM resells Cisco and Blade Network Technology switches and adapters made by Broadcom, NetXen, and QLogic. Voltaire makes the InfiniBand adapters for the BladeCenters, and Cisco makes the 4X InfiniBand switch IBM resells for its chasses. Voltaire is working on a 4X InfiniBand switch for IBM's blades. (IBM has five different blade enclosures, and all of them support the same blades even as they have been tweaked for different environments, such as ruggedized DC-powered variants or standard AC-powered commercial units.)

Several months ago, IBM announced an adapter card for its blade servers that put 8 Gb Fibre Channel (two ports) and Gigabit Ethernet on the same card; it had already been selling a similar adapter from QLogic that put two 4 Gb FC ports and a single Gigabit Ethernet onto the same adapter. Yost says that Brocade is cooking up an 8 Gb adapter for BladeCenter blades, which Big Blue will announce in the coming months.

Last month, ServerEngines announced that it had begun shipping a 10 Gigabit Ethernet converged network adapter for IBM's blades, which allows companies to run the iSCSI protocol out to storage and 10 GE out to the network, all from the same adapter card. There's a PCI-Express version of the ServerEngines adapter that plugs into IBM's System x rack servers as well. So far, IBM is not reselling these adapters directly, but it is only a matter of time.

While HP sells its own 8 Gb Fibre Channel switch as well as one from Brocade for its c-Class blades, the only FC adapters I can find for the blades themselves come from QLogic and Emulex, and they only run at 4 Gb speeds. (HP also sells its own 10 Gb and Gigabit Ethernet adapters for blades, plus a Gigabit Ethernet adapter from QLogic and a 4X InfiniBand adapter from Mellanox.)

I have a feeling that the HP bottleneck that IBM is claiming exists based on its tests is not in the chassis at all, but in the FC adapter cards HP sells for its blades. And this can - and most certainly will be - fixed in relatively short order. HP has not provided feeds and speeds for the bandwidth of the c3000 and c7000 chasses used with its current c-Class blades.

Anyway, when all the blade server makers get end-to-end 8 Gb FC connectivity to market, the sales pitch will be the same, whether IBM, HP, Dell, Sun Microsystems, or whoever is doing the talking. Moving to 8 Gb adapters and switches will increase performance if customers need that or allow for consolidation of blades, adapters, and switches if workloads are stable.

Bootnote: Dell has taken exception to being painted with the same brush that IBM used on HP's blades and Fibre Channel infrastructure. Chris Fenner, product marketing manager for blade servers at Dell, says that it has been shipping end-to-end 8 Gb Fibre Channel for its M Series blade servers since December 2008. He adds that Dell also supports end-to-end 10 Gigabit Ethernet and dual data rate (2X) InfiniBand networking, and will launch 4X InfiniBand within a matter of weeks. ®