When officials at the Comal Independent School District in Texas chose to have students build and maintain an electronic portfolio of their work, it seemed like a great idea from an educational standpoint. But finding data storage space for 11,000 students proved to be a challenge. To solve the problem, Glen Rogers, Comal’s director of instructional technology, decided to implement a storage area network, or SAN.
SANs are the newest trend in optimizing network use and data storage. Instead of relying on the hard-disk capacity of its bank of servers for storage, a district instead uses a separate network of storage devices that can be accessed by any server on the local area network (LAN) and, by extension, any computer on the network.
The configuration of a SAN allows for new possibilities in the way data can be accessed. Picture a traditional LAN as a wagon wheel pattern, where users of a desktop computer on one spoke access data stored on a server located in the middle of the spokes, regardless of demands being put on that server. Now, place another wheel intersecting this pattern, the SAN. Suddenly, a desktop user can access information by taking a variety of paths to it, bypassing a server that is down or overloaded.
This simple idea can have a dramatic effect. By using space controlled by a SAN instead of allocating dedicated slices of space on a host of LAN servers, a network administrator can reassign storage space more quickly and easily. When a programming class is working on a major project that requires a lot of storage space, for example, it’s a simple task to reassign space to the class and then reclaim it when the project is over.
This feature has proven especially important to Carl Savage, director of technology for the Hurst-Euless-Bedford Independent School District in Texas. “I’m able to dynamically allocate space wherever we need it,” said Savage. That makes the SAN “a lifesaver for us.”
Separating storage from server also increases reliability while decreasing cost. Users whose data are stored on the SAN can access their files even while the network administrator has taken a LAN server offline for maintenance or replacement. And the separation of data from server means that schools can purchase “thin servers,” or servers with a minimum of hard disk space available.
Comal’s Rogers believes the increase in reliability saves his sprawling district both time and frustration. “It’s hard to drive an hour if a server goes down,” he said. Centralized storage on the SAN will allow data to reside where a school district’s IT staff members are, instead of across the district. This is especially important for a district like Rogers’, with a limited budget for IT professionals. “I’m not going to be able to get additional staff” anytime soon, he said.
Hurst-Euless-Bedford’s Savage also found cost savings to be a major benefit of implementing a SAN. When his district received a bond package in 1997, officials began looking for a more efficient way to manage the data needed by their 19,000 students, plus staff and administration. The district’s original plan was to install 40 or 50 servers in a server farm to handle its storage needs. But Savage said the purchase of the SAN hardware saved the district 30 percent on its budget for servers.
That’s not to say that a SAN can be implemented on the cheap. The actual storage device or devices can be pricey, and a district must be running a high-speed fiber network to access its data at sufficient speed. Also, districts without sophisticated IT personnel may find they need to hire consultants during the initial stages of the project.
As a case in point, Washington’s Spokane Public Schools recently installed a SAN and will be using it for the first time during the upcoming school year. Dennis Schweikhardt, manager of technology infrastructure, estimates it will cost the district $1.5 million over three years to bring SAN technology to its 35,000 students, 3,400 employees, and 54 buildings.
Schweikhardt believes the outlay is worth it to bring a greater degree of reliability to the district. “Criticality [of our data] has increased,” he said. Few would question a Fortune 500 company’s need for always-available data, but many people might be unaware that education—with its finite instructional time and fleeting teachable moments—has a need for reliability that is just as urgent.
All of these districts chose a SAN solution from XIOtech, based in Eden Prairie, Minn. SAN solutions also are available from major computer providers such as IBM, Compaq, and Dell.
Richard Blaschke is executive vice president of marketing for XIOtech. He summarizes the benefits of a SAN for a school system as threefold: cost, speed, and reliability.
First is cost, which is decreased in the long term by using a SAN. A district will cut costs by centralizing its data storage into a single pool, getting more bang for its storage buck. Also, “schools have stringent staffing budgets,” said Blaschke, and cannot easily hire an additional database administrator who might command a salary of $125,000 per year. A SAN is easier to administer by a single person.
Second is speed. With the capacity of hard disks doubling at an astonishing speed, organizations that are using servers for storage might face the “fat-disk problem”—no matter what the capacity, users still can perform only the same number of inputs or outputs per second. A SAN allows for multiple access points and, therefore, greater access speed.
Third is increased reliability. Blaschke estimates that from 85 percent to 95 percent of all network downtime is planned, for activities such as replacing a server, installing new software, or reconfiguring memory allocation. By allowing for “hot swapping” and dynamic memory allocation, a SAN could cut planned network downtime dramatically.
As with all technologies, a SAN is not for every district, and it is not to be entered into lightly. “Don’t rush into anything,” advises Savage. After all, installing a SAN will entail a significant upfront cost outlay. But the benefits for your district might well outweigh those costs.
Links: Comal Independent School District
Hurst-Euless-Bedford Independent School District
Spokane Public Schools