Microsoft's NAS hurdle

The rise of storage-area networks (SANs) has changed the role of network-attached storage (NAS) devices, and so too has a technical directive from Microsoft Corp.

Microsoft's Exchange 2000 Server "will require a block-mode device," said Marc Padovani, a product manager at Dell Computer Corp. Consequently, file-oriented NAS customers and vendors face significant modifications to get their solutions to work with Exchange 2000.

Mark Amelang, director of marketing at Auspex Systems Inc., said one way to fix the problem is to tweak the Exchange server so it points to a NAS server, not a directly attached storage device, when it needs flat file data. But that tweaking is unauthorized by Microsoft, according to Amelang. If Microsoft finds that the server has been modified to deal with NAS, the company won't provide support, he said.

The word from Redmond, Wash.? "Microsoft generally recommends that you use a channel-attached disk storage system — SCSI, Fibre Channel or integrated device electronics — to store your Exchange 2000 Server database files, because this configuration optimizes performance and reliability for Exchange 2000," according to Microsoft's Web site. "By default, the use of network database files, which are stored on a networked server or network-attached storage server, is not enabled on Exchange 2000."

Auspex, however, has teamed with Educom TS Inc. to avoid the compatibility issue. Educom's Exchange Archive Solution enables Auspex's NAS box serve as an archive for old e-mails, without modifying Exchange, according to Amelang.

In addition, Network Appliance Inc. offers a software solution called SnapManager that allows its NAS appliances to be used with Exchange, according to Mark Santora, the company's senior vice president for worldwide marketing.

Padovani, meanwhile, believes an emerging network storage protocol, iSCSI, will provide another Exchange 2000 option.

"ISCSI will be used predominantly for Exchange applications and remote mirroring arrays," he said. But he doesn't expect to see a viable iSCSI/Exchange solution this year.