Make an iSCSI SAN with a USB key

An intriguing open source technology lets you turn old servers and their direct-attach storage into a NAS or SAN.

As iSCSI continues to find its niche in storage environments, users have a raft of choices when it comes to methods of deploying iSCSI storage area networks (SAN), from pre-packaged offerings by legacy vendors to free downloadable target software. Two users who have rolled their own iSCSI SANs using Linux-based software from Open-E GmbH said the product is a more affordable alternative than prepackaged systems and offers better support than free iSCSI target software.

Shon Nixon, chief, information technology for a company that designs iron processing plants, said his company first began using Open-E's iSCSI target last year as a way of dipping a toe into the IP storage waters.

Now, Nixon said, the company has around 1 terabyte (TB) of storage on its Open-E iSCSI SAN, which is based on a RAID subsystem from Infortrend Technology Inc. It's currently being used for disk-based backup of a production EMC Corp. CX3-20 and as a test bed for virtual machines. The company plans to add Open-E's Data Storage Server (DSS) to another Fibre Channel Infortrend RAID system for disaster recovery using Open-E's replication feature.

"Instead of $US100,000 to EMC, we're using a low-cost Fibre Channel array and avoiding replication license costs," Nixon said.

Open-E's product comes in three flavors: iSCSI, network attached storage (NAS) and multiprotocol, called iSCSI-R3, NAS-R3 and DSS respectively. The product, essentially an open source counterpart to Microsoft's Windows Storage Server software, uses a Linux kernel embedded on a USB key that attaches to a server to turn its direct attached storage (DAS) into an iSCSI SAN, NAS or both. The product also allows iSCSI access to Fibre Channel disks. The operating system and drivers for the Open-E software are housed on the USB flash device and don't require installation on disk.

A license for NAS-R3 costs $US995, iSCSI-R3 costs $US689 and DSS costs $US1,250. Each initial license contains support for 16 TB of capacity and includes unlimited free support and software features, such as snapshots and replication. Future software features added by Open-E will be offered as free upgrades.

A newly updated version of the software announced July 30 allows users to expand the initial 16 TB volume using license keys available in increments of 4 TB, 8 TB, 16 TB, 32 TB and 64 TB. Storage extensions are priced at $US189 (4 TB) to $US2,310 (64 TB).

The fact that the Open-E system doesn't have to be installed onto disks within the subsystem is also a plus for disaster recovery, Nixon said. "If my EMC SAN comes to a screeching halt in my production environment, I can just point my servers back at the DSS," he said.

According to Scott Montgomery, network support engineer for a fiber board and flooring manufacturer, his company is using the Open-E iSCSI-R3 product as primary storage for a 2 TB Exchange database, as well as for 3 TB of storage at a secondary location. The USB key is mounted on a whitebox RAID 5 server with SCSI disks at the remote location and a Dell Inc. PowerEdge 2950 server with SATA disks at the company's primary location.

Like Nixon, Montgomery said he likes not having to install an operating system or drivers on disk. "It makes it easier to set up and maintain the system, and if one of my servers fail, I can just unplug the key from its motherboard and put it onto another one without having to reinstall the operating system and drivers."

Montgomery also said he found the Linux-based product more appealing than Windows Storage Server, as he feels Linux is a more stable operating system. The product is less expensive than packaged iSCSI SAN products from LeftHand Networks Inc. and EqualLogic Corp. but includes free unlimited tech support and more free features than a free iSCSI target from Nimbus Data Systems Inc. (Nimbus offers 50 days of free support to users of its free iSCSI SAN targets and initiators, and offers an upgrade to its Breeze iSCSI SAN product if users want data protection features.)

Open-E aims higher

Open-E hopes its products will wend their way from the small business market to broader commercial use, according to Todd Maxwell, director of global product support services. Originally, Open-E had three versions of its product, one for prosumers and small office/home office (SOHO) users, one for small and mid-sized businesses (SMB) and an enterprise edition. As of this year, however, the two low-end versions, as well as a version of the software that used an IDE interface, have been discontinued to focus on enterprise sales.

But the product has yet to support or has only recently added software features expected in enterprise products. For example, in a software update announced yesterday, the product has added access control for replicated volumes and write-back for asynchronous replication. Previously, the system included licenses of Symantec's Backup Exec or EMC's Retrospect for backup, but only the latest release of the software supports tape rewind, delete and eject. The company claims installations as large as 80 TB, but before the expansion licensing introduced this week, each system was limited to 16 TB increments for management.

Meanwhile, Maxwell said other features, including centralized management and reporting for multiple systems, server failover and thin provisioning, are on the roadmap for this calendar year.

Open-E had yet to show up on the radar of storage industry analysts -- few contacted by had heard of the company. Those who had, doubted it has much of an opportunity at the higher reaches of the market.

"It's cool technology," said Greg Schulz, founder and analyst with StorageIO Group. "But it's a huge market out there with a lot of players, including Microsoft, and users can find free versions of similar technology. 'Cool technology' doesn't necessarily translate into business."

Another analyst, Stephanie Balaouras, senior analyst with Forrester Research, said users looking for cheap-to-free storage products should also consider built-in features from application vendors, such as Microsoft and Oracle. "Oracle has always claimed that customers really don't need to go out and buy expensive high-end storage, that there isn't any functionality they couldn't provide through Automated Storage Manager (ASM)," she said. "I think the server-tier vendors [such as] Symantec, Oracle, Microsoft [and] VMware are [currently] in a much better position to co-opt storage administration into their consoles ... storage and servers are merging again."

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