There are many potential benefits of IP SANs based on iSCSI, but relatively low cost is the primary factor.
By Michele Hope
Consolidation. Low-cost replication. Easier management. Familiarity with TCP/IP-Ethernet. The advantages of IP SANs based on the iSCSI protocol are by now a familiar litany to most storage administrators and managers. And although all of those advantages play a part in end-user adoption of iSCSI, low cost (relative to Fibre Channel SANs and direct-attached storage, or DAS) is by far the leading driving force, as shown in the following end-user case studies: Concourse Communications, Rothberger Johnson & Lyons LLP, Air Routing Group, SKMC, Frommer Lawrence & Haug LLP, GSI, Koch Logistics, Bellarmine College Prep, American Web Services, Ace Asphalt of Arizona, and Landrum Companies.
Systems and network engineer
Business: Designs and deploys wireless neutral-host networks in airports and large commercial venues
iSCSI implementation at-a-glance: FalconStor iSCSI Storage Server for Windows software, SATA drives
Applications: Microsoft Office, SQL Server, Exchange, custom applications for monitoring/logging wireless network performance
SAN capacity: 1TB
Primary driver for iSCSI adoption: DAS model unable to meet previously agreed-upon disaster-recovery SLAs with partners.
Benefits: Saved more than $100,000 versus Fibre Channel SAN; faster backups vs. tape, using snapshots for SQL Server and Exchange; on-the-fly provisioning without performance degradation
Concourse Communications knew its 30 servers with DAS could not be restarted quickly during a disaster. According to systems and network engineer Brandon Hoffman, the company also wanted to incorporate more enterprise-class technology, despite its small size. An iSCSI SAN fit Concourse’s requirements, allowing it to achieve centralized backups and data management, higher availability, and better disaster-recovery capabilities. Hoffman plans to add a second FalconStor iSCSI Storage Server in a separate location and mirror data between the two systems.
“iSCSI is modular and affordable and runs on our existing IP network,” Hoffman explains. “We also liked the fact that FalconStor let us choose any disk to run with its iSCSI Storage Server, including IDE, SATA, Fibre Channel. We didn’t like the rigid design some vendors dictated, where they said, ‘You have to use our box, and our disks.’ I needed it to be open and flexible. If something breaks, we wanted to be able to go to the local PC shop and slap in a new component.”
Rothberger, Johnson & Lyons LLP
Business: Law firm
iSCSI implementation at-a-glance: EqualLogic PS100E running on Novell NetWare LAN
Applications: Summation (litigation database software), clustered Novell print/file services, e-mail, and DHCP services
SAN capacity: 3.5TB
Primary driver for iSCSI adoption: Better IT responsiveness to last-minute storage demands for new cases under review; desire to cluster-enable servers for higher availability; direct support by Novell for iSCSI; lower cost compared to Fibre Channel
Benefits: Estimated 20% to 25% cost savings vs. Fibre Channel SAN; can easily provision large chunks of new storage to accommodate last-minute case load requests
After 11 years at RJ&L, IS manager Stephen Taylor had seen the company’s storage needs go from about 6GB for word processing files to almost 700GB, and counting. The primary culprit was the move to scanning paper documents for cases.
When scanned documents first began appearing, Taylor realized the company’s DAS configurations could not respond adequately to sudden requests to upload several CDs’ (or hard drives’) worth of data that had been dropped off for attorney review in a case. After trying a NAS system for a while, Taylor heard about iSCSI and knew it was time to start taking more proactive control of the situation.
Novell certification was important, which narrowed his list of vendors to EqualLogic. Since making the move, the iSCSI SAN has been able to accommodate several high-profile cases. “These revolved around hundreds of thousands of scanned pages of documents our attorneys needed to look through,” says Taylor. “When they started dropping off hard drives full of documents, we were able to say, ‘No problem. We have as much disk space as you need.’ ”
Air Routing Group
Senior network engineer
Business: 24-hour air traffic and weather monitoring and air travel services encompassing air security and corporate flight operations, scheduling, routing, refueling, and management
iSCSI implementation at-a-glance: Two Intransa IP5500 storage systems with SATA drives
Applications: Proprietary monitoring and tracking applications, most based on Microsoft SQL Server clusters; Exchange clusters
SAN capacity: 8TB (4TB per system), expanding to 12TB
Primary driver for iSCSI adoption: Easier data replication and rapid fail-over to remote disaster-recovery site; consolidated storage to accommodate rollout of new services and an estimated tripling of customer base over the next 12 months
Benefits: Rapid storage provisioning; reduced downtime; implemented 2x the storage capacity-and replication-for less than half the price of a 4TB FC SAN (without replication)
Air Routing’s senior network engineer Larry Newman was tired of waiting several days each time he needed to upgrade one of his DAS servers with more storage. “If SQL Server isn’t running for some reason, planes are in the air, but people can’t do their jobs,” he says. “Moving to a SAN was the next logical step for maintaining our business continuity. Another main concern was replicating data to a disaster-recovery site.”
With Fibre Channel costs too steep, Newman decided to evaluate three IP SAN vendors. He liked Intransa’s remote replication functionality and also liked that he could assign a unique IP address to every device on the system. This makes it easy to use third-party software to automatically ping IP addresses. If something isn’t available, the software notifies him automatically. Now, if SQL Server or the SAN itself goes down, his systems can be back online in about 30 minutes. Newman also replicates data asynchronously from one IP5500 to another system off-site.
Business: CPA firm
iSCSI implementation at-a-glance: IP SAN based on Variel Technology’s VXi800 iSCSI storage system with iStor’s GigaStorATX controller and SATA drives; Microsoft iSCSI software drivers
Applications: Various accounting packages (CCH, MS Great Plains, etc.); SQL Server
SAN capacity: 2.4TB
Primary driver for iSCSI adoption: Running out of capacity on DAS servers; lower cost vs. DAS and Fibre Channel SAN
Benefits: More available capacity; enabled disk-to-disk backup; eliminated network-related bottlenecks; reduced capital and ongoing management costs
The SKMC CPA firm, in Los Angeles, was running out of disk space on its DAS servers as it moved from paper to document scanning with a resulting surge in capacity. “We wanted to keep our servers, but upgrading the internal storage posed problems,” explains Ken Sousa, a partner at SKMC. Sousa considered NAS, but it wasn’t a good fit for some of the firm’s applications, such as its SQL Server-based apps.
“A traditional [Fibre Channel] SAN was way more than we wanted to spend,” says Sousa. The company opted for an iSCSI SAN based on Ariel Technology’s VXi800 storage system, which in turn is based on iStor’s GigaStorATX GbE iSCSI-SATA controller and 2.4TB of initial capacity. (Ariel is a systems integrator in Irvine, CA.) Five Windows servers are attached to the IP SAN, each running Microsoft’s iSCSI software initiators.
According to Sousa, the iSCSI SAN eliminated the network bottlenecks that the firm had been encountering with its DAS setup and also made it easy to switch from tape-base backup to disk-to-disk backup (although tapes are still used for off-site disaster recovery). Sousa estimates initial cost savings of $3,000 to $6,000 compared to growing capacity via server-based DAS. “And the iSCSI SAN is much easier to administer, which will lead to reduced ongoing management costs,” he adds.
Frommer Lawrence & Haug LLP
Business: Law firm
iSCSI implementation at-a-glance: Network Appliance FAS270C cluster with iSCSI support
Applications: Microsoft Exchange, Summation (document/image discovery), document management system
SAN capacity: 1TB
Primary driver for iSCSI adoption: Exponential growth in storage requirements for e-mail and document discovery systems; needed to support last-minute attorney requests for large quantities of extra storage
Benefits: Document retrieval now 30% to 50% faster; nightly document management system re-indexing can be completed in one-third the time
After struggling for years with his firm’s mounting storage needs, IT director Greg Indelicato was ready for an IP SAN. He had already gone from DAS to a NAS environment with Snap Servers. As the NAS appliances began to proliferate, he started experiencing many of the same growth issues. He was even starting to run out of physical space in the computer room.
Being a Microsoft shop, Indelicato was drawn to iSCSI. Indelicato went with Network Appliance after seeing the vendor’s snapshot technology and its Single Mailbox Recovery for Exchange software, which allowed him to restore the contents of individual mailboxes. He also liked how well he could respond to attorneys’ last-minute storage increase requests. “You never really know how much space you’ll need in a litigation,” Indelicato explains. “A week before electronic documents arrive, we’ll be told they need 10GB. Now, I can just increase space on-the-fly and decrease one volume and add to another. As opposed to buying more hardware, I can accommodate all cases on this one FAS device.”
Business: Data-center operations hosting and service provider
iSCSI implementation at-a-glance: EMC CX300i with Fibre Channel drives; QLogic QLA4010C iSCSI HBAs
Applications: Windows file shares, SQL Server clusters, Exchange clusters
SAN capacity: 2TB (adding another 4 to 6TB in the next year)
Primary driver for iSCSI adoption: Better SAN performance with clustered SQL Server applications; lower cost than Fibre Channel
Benefits: Between 300% and 500% faster SQL Server cluster performance vs. legacy DAS environment; estimated iSCSI per-port cost savings of 80% vs. Fibre Channel; enables meeting customer SLAs for service responsiveness via the ability to deploy new devices in 30 minutes to any part of the data center
To CTO Robin Greenhagen, iSCSI seemed a natural way to move to SANs. “iSCSI is really easy to deploy, and my team already knew Gigabit Ethernet,” he says. Once he compared iSCSI’s per-port cost vs. Fibre Channel, the deal was done. “Long term, I can envision us having 60 to 100 devices running off the SAN for what we would have spent to put 10 or 20 devices on a Fibre Channel SAN,” says Greenhagen.
GSI decided on EMC as its IP SAN vendor after asking its data-center customers which vendor they used for many of their own Fibre Channel SANs. He began with Fibre Channel disk drives, but now plans to add lower-cost SATA drives in his next upgrade.
“iSCSI demystifies the implementation of high-speed storage in small and medium-sized environments,” says Greenhagen. “Almost all of my engineers know GbE, and only a few know Fibre Channel. That really reduces the burden from a technology perspective.”
Senior systems engineer
Business: Freight brokerage
iSCSI implementation at-a-glance: Clustered iSCSI SAN with ATA drives from LeftHand Networks; Adaptec 7211C iSCSI HBAs
Applications: Microsoft Office files, SQL Server-based document imaging system with products from Pegasus Imaging Systems and Gauss Interprise; Maddocks Systems’ TruckMate ERP system on IBM DB2
SAN capacity: 3.37TB
Primary driver for iSCSI adoption: DAS servers at capacity, difficult to provision; needed better disaster recovery/fail-over for new ERP system; iSCSI SAN had the speed, redundancy and fault-tolerance needed, at a low cost.
Benefits: Provisioning new storage takes less than 10 minutes, as opposed to several hours with DAS; monthly DB2 maintenance dropped from 12 hours to less than 2 hours
To senior systems engineer Bruce Waslie, the choice between implementing a Fibre Channel or iSCSI SAN was really no choice at all. “We bought our GbE switches for $300 to $400, compared to the $7,000 or $8,000 we would have paid for a Fibre Channel switch,” he says. “I had worked with Fibre Channel SANs in a previous life, but discarded Fibre Channel up-front for cost reasons.”
Among the iSCSI contenders, the LeftHand SAN’s replication capabilities ultimately tipped the scales in LeftHand’s favor: It could perform both two- and three-way replication to more than one location. Waslie started with 1.7TB and three Network Storage Modules (NSMs), but soon added three more NSMs at a second building. “I introduced them to the cluster and reordered them. The only message I got during the process was that the volumes were being re-striped. Now I can fire up our DB2 server and run our ERP system from the other location.”
Bellarmine College Preparatory
Business: Secondary school
iSCSI implementation at-a-glance: Four Rasilient RASTOR 4000 iSCSI storage systems with SATA disks, supporting a server blade architecture from 3Up Systems
Applications: Microsoft Windows file shares, Windows Media Services, Exchange, SQL Server
SAN capacity: 12TB
Primary driver for iSCSI adoption: Upgrade from aging DAS storage to accommodate growing storage requirements from multimedia-rich teaching applications; shift to disk-based backup; upcoming migration to server blades prompted adoption of affordable iSCSI SAN storage
Benefits: Better performance than DAS, with less cache
IT director Chris Carey knew that a SAN was what Bellarmine needed to support its increasing use of online computers to address the different learning styles of its students. He concluded that the school was too budget-strapped to consider a Fibre Channel SAN.
Carey was dealing with audio files exchanged between foreign language teachers and their students, video production work, and a year’s worth of digital photos slated for the school’s yearbook. “When IP SANs came to market, we knew that was what we needed,” he says. Carey uses Windows Server’s DiskPart command to expand volumes and has begun to explore virtualizing existing volumes with Windows Servers’ Dynamic Disk function. “A lot of SAN solutions have way more features than you really need,” says Carey. “Rasilient has positioned its product as a Swiss army knife that you can hook up to a virtualization service, if you want, which works well for us.”
American Web Services
Chief technology officer
Business: Web hosting/design services provider
iSCSI implementation at-a-glance: iQstor iQ1250 iSCSI storage system with SATA drives; QLogic QLA4010 TOE cards (iSCSI HBAs)
Applications: Web applications including Windows ASP .Net, Microsoft CRM, SQL Server, Aeroclick, VoIP, mail services and Stalker Communicate e-mail system, DNS
SAN capacity: 2TB
Primary driver for iSCSI adoption: Migration from Windows 2000 to Windows 2003 required upgrade from aging DAS infrastructure
Benefits: Better data protection: Backups now performed hourly (via snapshot), instead of daily; estimated savings of 40% to 50% over alternative investment in new server cluster with DAS; faster read/write access times from SAN than from local hard drives
CTO Ed Williams was an early adopter of iSCSI-based IP SANs because they enabled an affordable upgrade for his firm’s entire server environment, as well as the ability to consolidate storage for better performance and management. “I knew if I just invested in the storage and made sure it was redundant, I could stack a bunch of servers on the front-end that had the processing I needed,” Williams explains. “The front-end servers have no local hard drives and no RAID cards, which generates a lot less heat. They all just boot off the SAN.”
QLogic TOE cards were added to aid in SAN boot functionality. The HBA accelerators are also used to process high-transaction loads (which can peak at 2,000 to 4,000 IOPS). The iQstor system was one of several iSCSI contenders on Williams’ short list. It was a little more expensive than the others, but Williams was impressed with iQstor’s breadth of software “goodies” and the system’s expandability.
Ace Asphalt of Arizona
Chief information officer
Business: Paving and maintenance contractor
iSCSI implementation at-a-glance: StoneFly IP SAN with IDE and SCSI disks; Alacritech SES1001 and SES2000 iSCSI HBAs
Applications: Microsoft Exchange, SQL Server, SalesLogix (CRM), Windows file storage, custom applications
SAN capacity: 4TB
Primary driver for iSCSI adoption: Six server failures with DAS over a 12-month period prompted search for a more high-availability SAN architecture; chose iSCSI over Fibre Channel due to lower cost and existing expertise in IP technology
Benefits: No storage-related downtime since implementing IP SAN; estimated support savings: $15,000 to $20,000 per year; disk-based snapshots replaced tape as a primary backup medium
“In the same year, we had every type of storage failure you could think of spread across 12 different servers,” recalls Darin Soll, Ace Asphalt’s chief information officer. After adding up the support costs involved in fixing the servers with their DAS, he knew it was time to look closer at IP SANs.
Ace Asphalt turned to Dell for help, which first put them in touch with a Fibre Channel SAN vendor that had a few too many zeroes at the end of the price quote, according to Soll. After then evaluating and discarding NAS due to potential performance issues associated with Exchange and SQL Server, Dell convinced Soll to look at StoneFly’s IP SAN offering.
As opposed to the Fibre Channel quote, StoneFly’s bid of less than $25,000 was more in line with Soll’s budget. He began with a 1TB system and soon added a second 2TB array with data synchronously mirrored between the two systems. “We’ve been thrilled with the performance, especially at the price,” says Soll, “but I’m more thrilled I don’t have engineers running around rebuilding servers.”
Britt Landrum III
Chief technology officer
Business: Staffing and professional employer organization
iSCSI implementation at-a-glance: Sanrad clustered V-Switch 2000 direct-attached to Nexsan Technologies’ ATABoy2 array with ATA disks and 2Gbps Fibre Channel connections; Alacritech TOE accelerator cards (iSCSI HBAs)
Applications: Microsoft .NET applications; CRM; PaperWise document management systems; Thoroughbred Basic custom databases (in process of migrating to SQL Server), Exchange, Windows fileshares
SAN capacity: 2TB
Primary driver for iSCSI adoption: Wanted to move to a SAN to meet requirements of new imaging and Web applications, and an estimated tripling of storage requirements in the next 12 months; iSCSI made the SAN move affordable
Benefits: Saved an estimated 50% investing in iSCSI vs. Fibre Channel SAN; better reliability, fail-over, disaster recovery, and replication functionality vs. prior NAS systems
Landrum has only about 125 employees, yet it has to perform many of the same functions as much larger companies, such as managing payroll for more than 11,000 employees comprising AmStaff Human Resources, and another 2,000 employees per year in Landrum Staffing Services. Then there are the warehouses of documents waiting to be scanned. With storage growth estimates going through the roof, an affordable IP SAN began to appeal to CTO Britt Landrum III and senior network administrator Jason Heuer. Although the firm had already made the switch from DAS to NAS filers, it continued to experience issues such as drives crashing, slow performance, and difficulty in adding new storage. It was also nearly impossible to replicate or reconfigure the storage from one device to another. That’s changed since Landrum implemented an iSCSI SAN. “With Sanrad’s switches, you just add more storage to a volume, reconnect to the iSCSI target and, boom, it’s done in about five minutes,” says Heuer. “And with iSCSI we have replication functionality. Sanrad has a neat fail-over to remote sites. Since it’s IP-based, you can replicate over a LAN easily and securely.”
Michele Hope is a freelance writer. She can be contacted at firstname.lastname@example.org.