Users Embrace NAS Benefits
Network-attached storage (NAS) promises a number of benefits, including faster file services, increased reliability, and lower costs, but it`s been a long time coming.
Enron Capital & Trade Resources (ECT), the financial arm of Houston-based Enron Corp., is one of the largest buyers and sellers of energy and energy services in North America. Its 150 traders buy, sell, transport, and store natural gas, crude oil, natural gas liquid commodities, and power.
Working feverishly to execute as many reliable transactions as possible, ECT traders constantly access and share market prices, trends, and other information. Just 10 minutes of downtime can result in catastrophic loss of revenue for the company. Jarod Jenson, ECT`s technical manager for Unix operations, estimates a loss of tens of thousands of dollars for each minute of server downtime.
While not every IT environment has such mission-critical characteristics, ECT`s scenario underlines the importance of data and the need to effectively manage, store, and access critical information.
ECT, which uses Sun Microsystems` servers as well as Auspex Systems` NetServer 7000, is one of an increasing number of companies implementing network-attached storage (NAS) solutions. Michael Peterson, president of Strategic Research, a market research firm in Santa Barbara, CA, defines NAS as "a storage array that connects directly to the messaging network via a LAN interface (such as Ethernet) using common communications protocols. A NAS device functions as a server in a client/ server relationship; has a processor, operating system, or micro-kernel; and processes I/O protocols, such as SMB or NFS."
The Specialization of Storage
First, a little history. The client/server model transformed the role of storage within computing environments. To stay competitive in a global market, companies shared information across workgroups. When end users started demanding file-sharing capabilities and faster access times, other factors became important (e.g., the performance of processors, storage devices, and I/O), so IT staff started implementing multiple processors and began placing storage units across the network.
As LANs grew, several shifts occurred. Networking products became more specialized, and network communications tasks were offloaded from general-purpose servers to routers and switches. Meanwhile, the growing LAN environments put pressure on storage vendors to develop subsystems with better I/O rates and network-wide access.
That`s when NAS servers started to appear. In contrast to general-purpose servers with massive operating systems and bloated application software, NAS servers, or "appliances," are designed to perform one task very well--serve files. The rationale is conceptually akin to how we use kitchen appliances: We don`t ask our toaster to blend a smoothie; we just want it to make toast.
The off-loaded storage frees up CPU cycles and makes management easier because storage is now consolidated into subnets. And NAS servers are less expensive than general-purpose servers, so departments with specific needs can have their own servers.
NAS began as a niche market. Major storage vendors, including EMC, Hewlett-Packard, and Sun acknowledged its presence, but they did not enter the market with the force to draw others into the arena. In contrast, NAS pioneers such as Auspex Systems and Network Appliance bet their companies on the promise of direct network attachment.
"It wasn`t until data volumes had grown to such a large extent that end-users started feeling the pain," says Mary Nowak, marketing and communications manager for Auspex. "General application servers that had been converted to departmental servers could no longer fit the bill."
The new NAS servers gained "intelligence" as they evolved from simple peripherals hooked to hosts via SCSI connections to stand-alone servers equipped with optimized software and file system transfer protocols (NFS, SMB and later CIFS and HTTP).
Network Appliance`s Data ONTAP software, for example, uses a micro-kernel-based design to facilitate network data access and to alleviate bottlenecks. Software such as Data ONTAP strips away cumbersome administration responsibilities and provides open interfaces so existing client software or networking infrastructures do not have to be altered. When they are placed out on the network closer to users, a dedicated controller helps balance network traffic.
Banking on NAS
At some sites, the main benefits of NAS servers are increased performance and fault recovery. NationsBank-CRT, in Chicago, for example, was not satisfied with the performance of its traditional Unix servers. Administrators were concerned about how quickly they could get its storage servers, which service about 100 traders and hold some 1.5TB of crucial data, back on-line in the event of a failure.
Paul Canning, vice president of NationsBank`s network services, recalls his first meeting with Network Appliance more than five years ago. He asked a sales rep how fast NetApp`s server could reboot if the power supply was disconnected. "When he told me 45 to 50 seconds, I told him that if it didn`t happen that fast that they would be asked to leave." As promised, the server was back up running in 45 seconds, and after extensive testing, NationsBank-CRT bought some 70 NetApp "Filers."
Scaled down, dedicated servers enable storage servers to address the needs of particular departments or applications. Relatively low prices and a wide range of capacities allow individual departments to have their own storage servers, tuned for special needs.
Over the last couple years, demand for specialized servers has increased, largely due to the explosion of the Internet and intranets and the widespread use of data warehousing and heterogeneous networks. For some sites, the key advantage of NAS servers is rapid access to data-intensive files. For other sites, fault tolerance and data security take precedence.
NAS to the Masses
Specialized NAS servers include optimized proprietary software for high-speed I/O throughput and for file sharing across heterogeneous platforms. More recently, more scaled-down storage servers have emerged. Over the last few months, some NAS vendors have begun shipping "network-ready" or "thin-server" products that provide lower-cost options.
While ECT and NationsBank-CRT have successfully implemented enterprise-level NAS, industry observers agree that many smaller sites are eager to leverage the benefits of NAS in small to medium-sized environments. Thin-server vendors are attempting to bring NAS from the Fortune 1000 to the "Unfortunate 1000" by introducing turnkey solutions with lower price points and storage capacities.
For smaller work-group environments, the key benefits of NAS include ease of use, operating-system independence, non-intrusive addition or deletion to the network, and entry-level pricing that`s similar to adding a fancy fax machine.
Some vendors such as Legacy Storage Systems have taken the approach that clients should be able to access data from the network without having to go through a server. Legacy`s UDSS Disk Array and MicroNet`s Impact, for example, can be placed in a remote area of a network, giving local users quick access to data in situations that require a full-blown operating system or application. Legacy founder and CEO John Whyte says people should consider a NAS strategy if they need to consolidate storage or need some flexibility in configuring their network.
NAS Comes to Optical
CD-ROM servers are not normally associated with NAS technology because they`re considerably slower than disk arrays. However, some vendors such as Procom Technology and Micro Design International have found a niche for network-attached devices in CD-ROM environments. Cost-conscious environments, or sites that don`t have large or sophisticated IT staffs, are often attracted to the plug-and-play advantage of network-attached devices--not to mention their comparatively low price tag. Procom`s DataFORCE CD-ROM server, for example, lists for about $4,000. Last month, optical storage vendor Meridian Data introduced the network-attached Snap! Server, a 4GB RAID system that starts at $995. The server is designed to be plugged in, and browser-administrated setup is minimal.
Less-expensive, lower-capacity NAS options have other benefits, according to its supporters. Don Woods, business unit director of Mylex Corp.`s Network Power & Light division (NP&L) believes companies should have the option of easily adding storage to their existing systems. NP&L`s AutoNet thin-server engine, for example, allows users to add disk drives and to share capacity, regardless of which server and which operating system is being used.
Technologically, have thin-server vendors re-invented the wheel? No, says Mark Jones, director of technology at Rare Systems, a Dallas-based systems integrator. What`s important, says Jones, is that these technologies bring NAS to people who couldn`t previously afford it. "People are excited because prices are realistic. Since more companies can afford to implement [NAS], it`s more of a real concept to them now."
Factors for Consideration
Before IT managers implement a NAS strategy, industry experts suggest they first take a look at their specific requirements and their budgets. NationsBank`s technical services group, for example, knew they needed reliability and quick recovery from component failure. By knowing these requirements up-front, says Canning, the company had an easier time comparing NAS servers with existing servers.
For ECT, file sharing was critical. Also, like NationsBank, ECT needed the added security of failover. "One of the big tasks in our environment is sharing data. Outside of querying the databases, everything else the traders do is share data," Jenson says. "Because we rely so much on information sharing, if we can`t make our storage available all of the time it`s a big problem for our company."
With so many factors and options to consider, where do you start? In a recent series of studies, Peripheral Concepts, a research and consulting firm in Santa Barbara, CA, asked IT managers and staff to rank the most important attributes of storage solutions. Six characteristics consistently led the list: performance, connectivity, scalability, accessibility, manageability, and cost of ownership.
-Performance: Most users who have employed NAS have a difficult time quantifying exact performance gains. At NationsBank-CRT, Canning points out that the greatest measure of performance success is often silence from the traders.
- Connectivity: The increased use of Windows NT-based servers has led to the requirement for connectivity to shared storage systems. More than ever, employees need access to a variety of file systems. NAS devices support NFS, CIFS, and HTTP protocols for file transfers across Unix and NT systems and the Internet.
Another significant issue is how easily and quickly you can connect and disconnect your storage system to add an array or to fix a failed component. The purpose of rapid file access is lost if it takes hours or days to restore a network.
- Scalability: Such data-intensive environments as the Internet and data warehousing have caused storage demands to increase tremendously. According to Kuljeet Kalkat, Auspex`s senior director of marketing, their average customer doubles the amount of network data every nine months. To meet this demand, NAS devices need to be scalable.
- Accessibility: Guaranteed data access is often associated with mission-critical environments such as those described at ECT and NationsBank. However, accessibility is also critical for any environment that cannot withstand significant downtime. Storage features to consider include automatic fault detection and total system restoration capabilities.
- Manageability: Centralized management is critical. "For users, one of the biggest features [of NAS devices] is integrated storage management," says Bill Reed, managing director of Symbios` MetaStor division (which was recently acquired by Adaptec). "The easiest way to offer that is on a single, integrated storage platform that manages different types of storage resources."
NAS has become a lot easier to use over the past year. According to James Staten, a storage analyst with Dataquest, a market research firm in San Jose, "The Web helped make network-attached storage easier to use. Internet access has made it possible to manage these boxes through Web servers and browsers," he says. For example, an IT manager can monitor networked storage off-site with a laptop.
- Cost of ownership: Beyond initial hardware costs, ongoing storage management costs (e.g., manpower costs) are generally the greatest expense. If storage implementation and management costs are tallied and broken down into a cost-per-GB matrix, users can determine whether NAS devices are cost-effective options for their enterprises. With more and more NAS vendors entering the market, other factors relating to cost of ownership that should be considered include service, support, and whether you buy direct or through the channel. Weighing these factors among the vendors will also help customers decide which solution is best for them.
"Differentiation from vendors will come in software and support," says Sean Derrington, senior research analyst at the Meta Group consulting firm, in Stamford, CT. "Support is especially important in NT environments."
Storage consultant Alvin Lehman agrees with Derrington, but believes the service and support offered by vendors should be extended into the channel. "Storage vendors need to make it easier for users and resellers to bring the systems up and manage them. If you make it easy to integrate, then [NAS devices] may eventually become commodities. But that`s still a long way off," Lehman says.
Booming Market or Unfulfilled Promise?
Despite its promise, NAS has failed to gain widespread acceptance. Anders Lofgren, an analyst with Giga Information Group, a consulting firm in Cambridge, MA, believes constantly changing definitions and terminology within the NAS market have caused confusion among potential customers.
Analysts also point to a cultural issue. Many IT managers often feel more comfortable going with name-brand server vendors and are hesitant to gamble on smaller, relatively unknown vendors. These analysts expect increased interest in NAS when large systems vendors such as Compaq, HP, and IBM offer mainstream NAS products.
And there are still other reasons why users are hesitant to embrace the NAS concept. "A lot of people want their data on their PC," says Kevin Liebl, vice president of marketing at MTI Technology. "They want it on their local drive so if the network is down, they can still get to it. So there`s still apprehension about giving up the local drive and putting all the data out on the network."
"NAS has been slow to take off because vendors are telling companies to buy another box, and in some cases to replace the servers they already have," says Staten. "I think NAS is going to catch on at the low end and work its way up through the enterprise. Small businesses will probably latch on to it first."
Staten`s prediction is beginning to come true. According to Dataquest, shipments of server appliances are expected to double from 1.5 million units in 1996 to around 3 million in 2000.
Network-attached storage servers are directly accessible from all servers and clients on the network.
The markets for storage-area networks (SAN) and network-attached storage (NAS) are beginning to boom, at the expense of the more traditional host-based storage architecture.
Many network-attached storage servers support multiple protocols, such as the Unix-based Network File System (NFS) and Windows NT-based Common Internet File System (CIFS).