By Kevin Komiega
Small and medium-sized businesses (SMBs) are adopting iSCSI SANs for many different reasons. Some organizations buy iSCSI technology for its ease-of-use relative to complex Fibre Channel SANs. Others dabble in IP storage as a way to build out a tiered storage architecture.
Derrick Arias, IT director for the City of Sunny Isles Beach, FL, and his team moved to a new facility in 2004 and soon found themselves tasked with supporting a wave of new applications. Arias started searching for a SAN to help get a handle on his data growth when it became apparent that he was going to have storage problems down the road.
“We manage all of the city’s technology. If it has an on-off switch it’s ours, and over the past year the number of applications we’re supporting has grown dramatically,” says Arias.
Arias didn’t take the bait when major vendors began dangling pricey Fibre Channel solutions in front of him. “We told the vendors that we needed something stable that can support SQL Server, but nobody could give me a straight answer as to why iSCSI was not going to be good enough,” he says.
That’s when Arias went the route of many SMBs and tapped his peers for advice. “We talked to other government organizations with much larger IT environments than ours that were running the same applications as we were. They were doing it with iSCSI. That’s when I realized I didn’t need to spend a million dollars,” he says.
The City chose Siafu Software’s Swarm IP SAN appliances, beginning with a 30-day evaluation. Test driving iSCSI SANs is a critical step in the evaluation process, according to Arias.
“If you’re going to buy an iSCSI SAN you have to try it out to see what the administration is like and make sure it will do everything you need it to down the road,” he adds.
The City’s Siafu Swarm 3000 IP Storage Appliance provides 3.25TB to 6.5TB of RAID 6-protected networked storage and supports VSS-integrated snapshots and disk-to-disk and disk-to-disk-to-tape backup. Swarm 3000 systems also come in high-availability configurations.
Ready for prime time
One of the arguments against iSCSI SANs is latency, but user adoption seems to be on the rise now that IP SAN technology has been fine-tuned for reliability and speed.
“It was always said that iSCSI was not mature enough or ready for prime time. Last year, I think it finally came into its own,” says Chris Simms, a network administrator at Clayton County Water Authority, in Morrow, GA.
The Clayton County Water Authority’s storage requirements are increasing due, in no small part, to a document management system based on EMC/Legato’s AppXtender product. The document management solution accounts for almost 1TB of storage by itself and doubled the Water Authority’s backup workload overnight.
With a careful eye on the price tag, Simms put out some feelers for SAN solutions. Much like the City of Sunny Isles Beach’s Arias, Simms relied on his peers for advice early in the evaluation process.
“I went to the Georgia Department of Transportation for a site visit. Their environment is larger than ours and I wanted to see the technology work,” says Simms.
He then worked with VeriStor Systems, a systems integrator based in Duluth, GA, to migrate from a direct-attached storage (DAS) to an iSCSI SAN environment.
“Fibre Channel just did not jibe with me because of its innate complexity and the hardware buy-in,” says Simms. “iSCSI is more basic. If you go into iSCSI do you really need a storage expert? Why re-invent the wheel? We’re not very I/O-intensive right now, and iSCSI fits with what we’re doing.”
Simms opted for a pair of PS300E iSCSI SAN systems from EqualLogic. The PS300E systems feature 7TB of capacity using 500GB, 7,200rpm SATA-II drives. Simms has one box running at the Water Authority headquarters and another off-site for disaster-recovery purposes.
Other features of EqualLogic’s PS300E include dual controllers (each with 64-bit dual-core RISC processors), support for RAID 5/10/50, automatic volume replication and load balancing, and multi-path I/O. EqualLogic claims performance of up to 60,000 I/Os per second and 300MBps throughput.
iSCSI for tiered storage
It is not always a Fibre Channel-versus-iSCSI argument in SMB environments. Implementing iSCSI SANs as a complement to a Fibre Channel network is an ideal solution for tiered storage architectures for some users.
Andrew Collins is a network engineer for the Denton Independent School District, based in Dallas-Fort Worth. Collins has a team of three administrators supporting 26 campuses, more than 19,000 students, and a total of 100 servers, some of which are attached to the district’s primary storage pool on a 10TB Xiotech Magnitude 3D Fibre Channel SAN array.
The Magnitude 3D supports critical applications such as e-mail and frequently accessed home drives, but data growth in other areas prompted Collins to look for low-cost alternatives to Fibre Channel.
“Fibre Channel storage is rather expensive,” says Collins. “There are a lot of users in our school district that need large amounts of storage space, but not necessarily expensive storage space.”
For example, the district’s high school students generate a large number of multimedia files on a daily basis. That’s why Collins brought in the Magnitude 3D’s little brother-the Magnitude 750-an entry-level iSCSI virtual storage system.
The Magnitude 750 delivers up to 12TB of capacity sharable by up to 24 application servers, all in a 3U rack-mountable chassis. It was a no-brainer for the district. The Magnitude 750 is built on the same architecture as its Fibre Channel counterpart.
“They are siblings in terms of the information that’s stored on both of the arrays. Both support mapped network drives for our users, but the Magnitude 750 hosts our media drives,” says Collins.
Collins was evaluating NAS and DAS solutions from multiple vendors, but none seemed to fit his cost, capacity, and scalability requirements. “Cost and scalability are important for us. The infrastructure was already in place for an iSCSI implementation because the servers we have all include dual Gigabit Ethernet network interface cards. They were ready to go for this type of application,” Collins explains.
Setting up a tiered architecture using iSCSI can also be accomplished by reclaiming existing Ethernet-based DAS.
Web services firm eFashion Solutions develops and maintains e-commerce solutions for a “who’s-who” list of fashion designers and photographers. eFashion administrates Websites, takes and fulfills orders, and provides customer service for fashionistas across the globe from New York to Tokyo. (The company also runs a Website called Shopelvis.com.)
“We have a photo studio on the premises. Digital pictures take up a lot of room and we were running out of space and trying to keep a handle on what we had,” says Daniel Falcone, eFashion’s senior network administrator. Falcone is responsible for eFashion’s day-to-day IT operations, as well as budgeting, planning, and implementation of IT projects.
“A lot of small businesses in my situation go out and look for the resources they need to do something. But if you go to a SAN specialist, they will sell you a SAN. To a carpenter, everything’s a nail,” says Falcone.
For Falcone, the key to choosing and buying a storage solution was to understand the differences between SAN environments, whether they be hardware- or software-based. “You have to look beyond the acronyms and understand the concepts behind the products you’re buying. The result is to make sure the products meet the specifications of what your business needs,” he says.
Falcone is taking a relatively new approach toward meeting those needs with QLogic’s SANbox iSR6142 iSCSI multi-protocol router, which supports both Fibre Channel (including FCP-SCSI and FCIP) and Ethernet/iSCSI (10/100/1000Mbps Ethernet).
eFashion is using QLogic’s SANbox 6142 as a bridge between its existing Fibre Channel storage and its Ethernet-based server storage to create a tiered storage architecture.
Falcone says his high-performance applications, including databases, are supported directly by Fibre Channel storage, while the iSCSI links serve lower-performance application needs, such as storing digital media and pictures.
QLogic’s SANbox iSR6142 Series multi-protocol routers allow users to connect remote servers over iSCSI to Fibre Channel-based disk and tape storage for consolidation and migration from DAS to SAN configurations.
Used in pairs, SANbox 6000 routers can also provide Gigabit Ethernet connectivity between Fibre Channel SAN islands, facilitating disaster recovery and other long-distance applications.
“It gives us the flexibility to expand our iSCSI array cost-effectively so that we’re not locked into buying all Fibre Channel storage,” says Falcone.
Part 2 of this series will run in the February issue of InfoStor.