E-mail management vendor Azaleos said Tuesday it is adopting new remote SAN booting capabilities from Microsoft in hopes of reducing the cost and complexity of maintaining distributed Microsoft Exchange deployments while increasing availability and disaster recovery options for the e-mail server.

Microsoft Tuesday unveiled support for software-enabled storage area network (SAN) boot of Windows using Internet Small Computer System Interface (iSCSI) and standard network interface cards (NIC), through technology co-developed by Microsoft and IBM.

The iSCSI boot technology is supported on Windows Server 2003, and IBM is offering support on its BladeCenter servers. The combination offers a level of availability, reliability, scalability and redundancy that previously was possible only with expensive host bus adapter network cards, which typically run from $600 to $800 for blade servers.

Azaleos is using its recently announced support of Network Appliance storage devices combined with three IBM blade servers to support disaster recovery and patching scenarios for its OneServer appliance, which runs Exchange. The appliance is deployed within a company, but managed remotely by Azaleos.

With the SAN boot technology, an iSCSI-attached SAN provides the source for operating system, applications, and data, which obviates the need for local storage on blades.

Users can remotely boot the diskless blade servers from a SAN device using an image of the operating system stored in a logical unit number (LUN) on the storage device. The LUN is used to identify SCSI devices so the host can address and access the data on each disk drive in an array.

The Microsoft iSCSI-enabled SAN boot technology requires a separate LUN for each blade. Storage virtualization technology called "snapshot" can be used to create multiple copies of a single image for storage on each LUN. The iSCSI technology also requires a change either in the server BIOS or in the NIC firmware.

Azaleos is building on those capabilities by allowing users to include OneServer as part of the image for booting the blade.

“This is useful for customers looking to support disaster recovery or branch office locations,” says Azaleos CTO Keith McCall. He says other benefits include rapid scale out of an Exchange environment and a 10% to 15% reduction in the cost of running three blade servers as opposed to three standard servers to support a rollout of OneServer.