EMC preps FCoE I/O module

EMC has confirmed industry suspicious that is developing a hot-swap Ultraflex FCoE module for its storage arrays.

Yesterday Chad Sakac, EMC's VMware Technology Alliance veep, revealed: "We’re now, of course, developing an ultraflex IO module for FCoE, which (is) hot-swappable."

FCoE (Fibre Channel Over Ethernet) sends Fibre Channel messages across an Ethernet cable and will enable faster overall transmissions because things happen lower down the network protocol stack than with iSCSI and NFS, which rely on TCP/IP, according to Sakac.

"Because of the intrinsic model of the protocol stack, the higher you go, the longer the latencies in various operations." He cites transmission loss handling as an example.

With FCoE, such loss handling is carried out at the Ethernet layer, via the coming 802.1Qbb standard, in milliseconds, whereas it can take tens of seconds for NFS.

UltraFlex is the name for the I/O technology used in EMC's Clariion CX4 arrays and newer Celerras. It provides a means to add new I/O protocols to the array by plugging in cards. The CX4 came with 4Gbit/s Fibre Channel and iSCSI modules. It meant that EMC could later add 8Gbit/s Fibre Channel, 10GigE, FCoE and even InfiniBand if it wished.

Until now NetApp has been the sole big storage array supplier to demonstrate an FCoE interface to its storage. Sakac has confirmed what many people have suspected, that EMC is indeed developing an FCoE module which will enable end-to-end FCoE links between servers, any intervening FCoE-handling Ethernet switch and the Clariion array.

Sakac thinks server edge networking will converge onto Ethernet, partly because Intel will support 802.1Qbb and provide a software initiator.

Because of this, FCoE support will "just be an attribute of every commodity NIC and switch on the market. Everyone in the FC HBA/switch market is rushing to it not because they want proprietary, but rather because we're reaching the inflection point where if you’re not doing this, you’re going to be out of business (maybe not today, but at a relatively near “tomorrow”)."

Currently, end-to-end FCoE is limited to 2-hop networks for now, server-to-switch-to-array. ®