Selecting the Right NAS File Server As the network administrator for a workgroup LAN, consider this scenario: once again, one of your network file servers is running out of storage space. You send out the usual broadcast messages for users to delete old files, but you know you have not eliminated the problem, only postponed solving it. It is time to rethink your options for increasing disk storage space. If your network server has an available drive bay, you might consider adding a hard disk. This sounds economical. But you will need to take the server offline, and you will hear from your users about that. After totaling up the time and effort it takes to reconfigure the server and probably sacrificing part of your weekend it may not add up to such a bargain. You could add more network storage with another PC server. That would put a bigger dent in your budget, especially after purchasing the usual operating system software licenses. Plus it will take a day or more of your time to configure the new server and integrate it into your existing network. Or you could consider a third alternative: a new network file sharing technology called network attached storage (NAS). NAS file servers expand storage capacity independent of the PC server and provide a simple, cost-effective solution to adding network storage. Traditional Ways to Add Storage Traditionally, organizations have addressed the need for more storage by adding disk drives to an existing server or installing a new generalpurpose server on the network. Both solutions can be time consuming for the IT professional and disruptive to the workgroup, since the server must be taken offline. To minimize the disruption, hardware upgrades are usually scheduled for off hours, requiring the IT staff to work evenings or weekends. However, in environments with demands for high data availability, there are few or no convenient windows of time for users to be without access to their network resources. In addition to the user inconvenience, any time spent adding storage is time that the IT professional is not available to deal with other network problems. 1
After hardware, software licenses, and installation time are considered, a new server for the workgroup can cost anywhere between $3,000 to $10,000, and it may take a day or more to install. Even after the new server is installed and tested, problems may occur once the system is on the network and put under load. A new disk drive may be relatively inexpensive, but installation can take several hours to half a day. As demands for data storage continue to grow, traditional methods of adding storage to the workgroup have become increasingly costly. The Evolution of NAS File Servers The personal computer has paved the way for network server technology. Over the last two decades, PCs have evolved into general-purpose network servers responsible for managing a number of complex functions including storage, application delivery, printing, and gateway functions. All activity is routed through this general-purpose server, taxing server resources and often creating a bottleneck. Throughput and response time suffer as a result. In an attempt to alleviate these conditions, system administrators have begun to modify general-purpose network servers to deliver a limited set of specialized functions. One such specialized need is file sharing. Many PC servers are configured with a large amount of storage and dedicated as online file repositories. Because of the general-purpose nature of PC server design, its deployment as a network file server carries unnecessary and unused components, not to mention the IT resources needed to fine tune a multi-purpose network operating system for a specific function. A Simple, Economical Way to Add Storage NAS file servers were developed as an alternative to the general-purpose server. They are single-purpose appliances, dedicated to serving files, which provide a flexible and inexpensive alternative for adding storage to the workgroup. NAS servers connect directly to the network, not to the file server, giving rise to the term network-attached. Workgroup users cannot distinguish between accessing files on a general-purpose server or on a NAS file server. The only difference a user might notice is improved network performance and the ability to access files even if the general-purpose server is taken offline. NAS server hardware has been streamlined, eliminating unnecessary components. This results in significant cost savings over general-purpose servers. For example, with a NAS server, there is no need for a keyboard, mouse, monitor, or I/O ports. NAS servers run a highly efficient operating system, typically with built-in support for multiple networking protocols, which has been optimized for serving files on the network. Unlike traditional servers, whose operating systems charge a per seat licensing fee for each user connected to the server, there are no licensing fees with NAS servers. The system software is embedded, and software upgrades are usually free via Web download. With a NAS server, you pay for only those hardware and software components that are needed for network storage. 2
Snap Server Family Network Attached Storage By connecting directly to the network, NAS file servers (like the Snap Server family from Snap Appliances) enhance network performance and reduce potential throughput bottlenecks. Applications for NAS Servers The primary uses for NAS servers are file sharing and online storage. Some workgroups use NAS servers to store large files near the user nodes that most frequently access them. This helps isolate network traffic and assists with network and server load balancing. Some organizations duplicate images of frequently-used software configurations and distribute them on NAS servers throughout the organization. This takes the load off the primary file server. Engineering and design firms have found that NAS servers provide an inexpensive solution for archiving CAD/CAM and other data-intensive files. The files are easily accessed when needed. Remote offices use NAS servers to increase online storage at their location. The installation is managed at the remote site, without requiring in-depth assistance from the corporate IT staff. Field sales personnel attach their laptops to the network when they are in their home office and download the latest versions of application software from a NAS server. This relieves IT staff from having to schedule time to load the software from a CD and ensures that the entire organization is using supported versions of software. What to Look for in a NAS File Server To meet the workgroup s increasing demand for data storage, NAS file servers are rapidly growing as a product category. They are easy to install and maintain, and they are more economical to own and operate than traditional, general-purpose file servers. Because these products are relatively new, it may not always be clear how to evaluate them compared to other traditional storage options. Which product features are important when choosing a NAS server? Which benefits should you expect? The following criteria will help you evaluate and select the best product for your workgroup LAN. 3
Easy Installation Adding a NAS file server to an existing network should be as simple as plug it in and turn it on. The default installation should take no more than five minutes. The NAS server should be easily installed and integrated into an existing network without disrupting other servers, and there should be no additional server or client software to install. Network users will have access to all their files and network resources during the installation process. Once your NAS server is out of the box (or attached to your rack), the system should be operational in no more than three steps: 1) Plug in the power cord; 2) Connect the Ethernet cable; and 3) Turn on the power. Compatibility with Existing Networks To ensure easy integration into an existing network, choose a NAS server that is compatible with your established networking protocols and workstation types. Check to see if the server can respond to a DHCP, BOOTP, or RARP server to receive an automatic IP assignment. If you opt for manual IP address assignment, look for an easyto-use installation wizard that will help you step through the task quickly. The better a NAS server supports your existing workgroup environment, the less time and effort it will take you to configure and integrate the new NAS server at installation. Advantages of NAS Servers Compared to Traditional File Servers Easy to install and maintain Lower cost and reduced total cost of ownership Improved price performance Data availability even if the primary server is offline Support for multiple client types (Windows, Macintosh, and UNIX/Linux) Free software upgrades via the Web Intuitive Web Administration Since a NAS server is specialized for a single function, it requires limited maintenance. Any routine administration or customization of the NAS server is easily performed via a simple Web browser from any client on the network or from anywhere on the Internet. In evaluating a NAS server, check for an intuitive, easy-to-use graphical user interface to the Web browser. 4
Cross-Platform File Sharing Cross-platform file sharing can be a headache for the IT manager in workgroup environments where there is a mix of Windows, Apple Macintosh, and UNIX/Linux workstations requiring support for Microsoft, Novell, Apple, and UNIX networks. To address this problem, some NAS file servers have been pre-configured to support more than one network protocol for cross-platform file sharing. A NAS server should appear on the network like a native file server to its clients with files saved and retrieved in their native file formats. To protect your investment in existing hardware and software, choose a NAS server that is pre-configured to provide concurrent support for those network protocols and workstation types already in use in your organization. Conformance to industry standards and compatibility with existing equipment will ensure an easy installation and the long-term use of the NAS server. Network Security If security is a concern on your network, choose a NAS server that integrates into your existing network security by supporting Windows domain controllers for pass-through security. Integration with Windows domain security for pass-through user authentication provides a superior solution over password security for network shares. Compatibility with an Established Backup Policy After storage and file serving, backup is the next most common use for a NAS server. There are two types of backup usage that should be considered during your evaluation: using the NAS server as a backup device on the network for workstations files; and using the NAS server as part of an archival solution for enterprise backup. Check to see if the NAS vendor offers a solution to back up workstation files onto the file server. In addition, the NAS server should be compatible with leading network backup application software used, or anticipated, in your organization. Improved Performance Under Load Data throughput under load is the single most important measurement of performance in a file server. Investigate how many concurrent users the NAS server has been tested to support and what kind of throughput is achieved under load look for independent lab tests and trade-magazine reviews. A NAS file server should be able to support at least thirty concurrent users comfortably, without experiencing a severe performance degradation or dropping network connections. When performance is an important consideration, choose a product that supports advanced disk configuration such as disk striping (RAID 0), where two or more disks are combined into one large, virtual volume and the data is striped across disks. 5
Component-for-component hardware comparisons between NAS servers, or between a NAS file server and a traditional file server are not a useful means of gauging performance. A NAS file server can offer equal or better performance at a lower price compared to a general-purpose server because it is optimized for a single function. The NAS file server requires significantly less processor power and memory than a generalpurpose server because there are far fewer tasks to perform and far less software to load and run. Because NAS file servers are highly optimized for their tasks, differences in software efficiency among vendors often make a bigger difference in performance than more obvious hardware differences. Network performance enhancements can also be expected when a NAS file server is added. Moving frequently-accessed files to a NAS file server reduces the load on the general-purpose server and helps eliminate potential throughput bottlenecks. Similarly, access to files on the NAS server will not be adversely affected by an unusually heavy workload placed on the general-purpose server. If the network is segmented, performance improvements can be further realized by locating the NAS file server closer to the workgroup, on the same network segment as its primary users, and isolating traffic to that segment. Specific performance benefits will depend on your network configuration and availability requirements, but you should experience improvements in load balancing with a NAS server. High Reliability Single-purpose NAS servers are more reliable than general-purpose servers, which are designed to handle diverse tasks. With NAS servers, all unnecessary components have been removed, resulting in a streamlined, highly integrated product. A higher degree of integration enhances the NAS server s stability, and fewer components reduce the risk of failure. The embedded operating system has been optimized for file system I/O and networking. When reliability is important, look for NAS file servers that support data redundancy features like disk mirroring (RAID 1) where the content of one disk is duplicated onto a second disk. Data striping with parity (RAID 5) is an important feature to look for in NAS servers configured with three or more disks With NAS servers, users have access to their data even if the general-purpose network server is unavailable. This in turn makes the network more reliable, reduces the load on the general-purpose server, and minimizes the exposure of a server outage. 6
Portable Storage Using the NAS server as a portable or temporary storage device enables a number of new applications. For example, the NAS server can be installed temporarily on the network and brought up as instant network storage while the general-purpose server is taken offline for maintenance. Or the NAS server can be used to store large graphical presentations and easily transported and installed at trade shows, customer sites, or remote offices. If the NAS server is being considered for applications like these, look for a lightweight device with a compact footprint. Family of NAS Solutions from a Reputable Vendor NAS servers address storage needs inexpensively and incrementally by providing services where they are needed. Multiple servers can be added to a single network. Ideally the NAS vendor will offer the user a family of solutions, ranging from a small single drive that could be used as a portable server to products with multiple disk drives in a rackmount chassis offering data redundancy features. Choosing a NAS server from a leading storage vendor ensures the availability of long-term support over the life of the product. Low Cost of Ownership The streamlined NAS server provides a reliable, cost-effective way to add storage to the network. And, because the NAS server includes its own operating system, there are no per seat licensing fees and no software update costs as there are with a general-purpose server. This results in significant cost savings when compared to an NT server. NAS servers also reduce dependence on IT staff. The self-contained NAS server is easily installed and stays up on an existing network. This frees the system administrator from the mundane chore of adding storage and maintaining another server, and allows IT managers to focus their time and budget on other critical system and network problems. Minimal administration requirements, support for cross-platform file sharing, integration with established network security, and compatibility with leading backup applications all contribute to a lower total cost of ownership over the life of the product. With a NAS server, users anywhere on the network from corporate headquarters to remote offices are assured of timely, reliable access to their data. And IT managers have a cost-effective file server that is easily integrated into an existing workgroup. 7
Giving Customers What They Need Hard Drive Snap Server NT Server Purchase Cost $600-$1,999* $499-$4,499 $3,000-$10,000 Installation Hours to days 5 minutes 1-2 Days User Downtime During Installation Server is offline None Unknown (could be days) Hassle Significant Minimal Frequent weekly reboots Required Expertise Professional IT knowledge * Includes installation time/fees. Basic PC literacy Professional IT knowledge NAS file servers, such as the Snap Server family from Snap Appliances, provide a simple, cost-effective alternative for adding storage to the workgroup. About Snap Appliances, Inc. Snap Appliances is the manufacturer of the Snap Server, a workgroup network attached storage (NAS) solution. The Snap Server product series includes the portable Snap Server 1000 15GB and 30GB, and the desktop Snap Server 2000 60GB. The Snap Server 4100 120GB and 240GB are rack-mountable products with RAID 5 capabilities to fulfill the storage needs of larger organizations. Snap Appliances, 2001 Logic Drive, San Jose, CA 95124, (408) 232-6831. More information on the Snap Server series is available at www.snapappliances.com. ### 2001 Snap Appliances, Inc. All rights reserved worldwide. All other company and product names are trademarks of their respective owner. NAS White Paper-Color/020601 5K 8