By Robert Stevenson, Doug Rainbolt, and David Dale
There is ample evidence that iSCSI can provide significant benefits to organizations of all sizes today.
-- A recent end-user survey conducted by TheInfoPro (TIP), an independent IT research firm, revealed several interesting findings regarding iSCSI adoption in Global 2000 organizations. It is well known that the use of iSCSI has consistently been associated with small and mid-size organizations looking to migrate away from direct-attached storage (DAS). Historically, many SMBs have been drawn to iSCSI due to its ease-of-use and low cost. These organizations hadn't invested in Fibre Channel, and iSCSI provided a relatively easy way to migrate from DAS to networked storage. In contrast, Global 2000 organizations made significant investments in Fibre Channel, and the roles and responsibilities that demarcated networking from storage were well defined.
Fast forward to today. The latest TIP survey indicates that large organizations are, in fact, using iSCSI and spending on iSCSI is rising rapidly. One question is, "How are Global 2000 organizations using iSCSI?"
In its most recent study - which details storage technology implementation timeframes and spending obtained via more than 150 one-on-one interviews with storage professionals - TIP found that approximately 16% of Global 2000 organizations have installed iSCSI storage. While this number is not all that surprising, given that this has been the general trend over the last four years, the feedback on users' experience with, and plans for increased spending on, iSCSI reveal some interesting trends.
When asked where and how iSCSI was deployed and used within these organizations, the overwhelming feedback was that increased spending was planned – by approximately 40% of the organizations – to further use iSCSI primarily to save money on replication and for use within remote-office storage environments. (Overall, 40% of the respondents planned to spend more on IP SAN arrays over the next year, 32% expected spending to remain about the same, and 28% planned to spend less on IP SANs.)
Though iSCSI is far from being the dominant SAN technology for large data centers, it is finding roots in several areas of the enterprise, including Windows environments with extensive file serving needs; large branch/remote office deployments where Windows is prevalent; and low-cost disaster recovery solutions for non-mission-critical data – especially in environments where data is widely distributed across a number of offices.
What has changed
According to the TIP survey, a traditional use-case scenario for iSCSI within large remote offices has been in the areas of replication, file sharing and email archiving; however, as organizations build out tiered storage, and as server virtualization continues to have a greater effect on all areas of an IT infrastructure, the place where organizations are deploying iSCSI has changed dramatically over the last year.
Many organizations have found that the use of iSCSI simplifies virtual server management, using the inherent advantages of IP in abstracting virtual servers from physical storage – making migration and reconfiguration easier. Its use has expanded beyond the local area, either as a pure iSCSI environment or in mixed environments with Fibre Channel fabrics. Where a year ago in such mixed environments iSCSI was deployed only through a gateway to Fibre Channel SANs in the local area, it is now being deployed through the WAN to Fibre Channel SANs as users leverage the distance advantages of IP storage. Within the local area, users are frequently connecting NAS gateways to iSCSI targets, and deploying end-to-end shared LANs and end-to-end dedicated LANs – with a focus on backup services, Microsoft SQL services, and file services.
The survey results reveal that large enterprises using iSCSI consider data recovery, file replication, and flexibility to be the key areas in which iSCSI excels.
"More and more users are finding that iSCSI is much easier to implement compared to alternatives in the marketplace," says David Stevens, a storage manager at Carnegie Mellon University. "iSCSI was faster for us to implement and required fewer people than competitive options, which resulted in reduced storage costs. I expect to see more and more organizations implementing iSCSI in the data center."
It is difficult to tell at this stage what the long-term future of iSCSI will be within Global 2000 organizations, although it is clear that organizations are seeing benefits that exceed initial expectations. Some organizations point to the future of Fibre Channel over Ethernet (FCoE) as being a key enabler that promises to unify fabrics, offering simplification, cost savings, and the preservation of assets.
The TIP study shows that many large enterprises are cautious when questioned about iSCSI deployment plans as they consider a possible future of FCoE. These are the same organizations that have made significant investments in Fibre Channel; therefore, the responses aren't surprising.
Nonetheless, large enterprises that have deployed iSCSI are finding benefit and are expected to continue to make investments in broader use of the technology. It is difficult to predict what the future will bring and whether it will be an FCoE versus iSCSI debate, with one having to win and one having to lose. Regardless of what the future may bring, there is ample evidence that iSCSI can provide significant benefits to organizations of all sizes today.
ROBERT STEVENSON is managing director of storage research at TheInfoPro. DOUG RAINBOLT is a board member of the SNIA IP Storage Forum and vice president of sales and marketing at Alacritech. DAVID DALE is chair of the SNIA IP Storage Forum and director of industry standards at NetApp.