The basic idea of NAS is to take raw storage and present it in a user-friendly format, usually through either Windows shares (CIFS) or Unix filesystem mounts (NFS). Other basic features include the ability to expand volumes on the fly, integrate with various security protocols (Active Directory, LDAP, etc.) and to support user quotas on the shares. Beyond this basic feature set, vendors such as Dell, EMC Corp., Hewlett-Packard (HP) Co., IBM Corp., NetApp and others tend to vary somewhat on the additional features they support as well as potential cost for those features. For example, features such as snapshots of the shares and support for NDMP backups of the NAS volumes to your existing tape infrastructure may require additional licensing.
Some vendors such as NetApp support data deduplication and others do not. Some vendors including EMC and NetApp provide complete data storage solutions with a NAS processing/access head and backing fiber or SATA disk drives; others, including ONStor Inc. (recently acquired by LSI), provide gateway appliances that attach to existing storage infrastructure. And still others, like Dell and HP, can provide a Windows Storage Server with direct-attached disk arrays. The key to implementing a properly sized and economical NAS solution lies in understanding these features and which ones are necessary for your business and IT objectives.
Do you need NAS?
The basic question small businesses must ask themselves is what is the objective of moving to NAS? For most SMBs, the benefits of implementing NAS into their data storage environment may include the following: consolidation of file server administration, technology refreshes, reduction of licensing and maintenance costs, and increased flexibility. For example, if the organization has a hard performance requirement for its shared storage resources, this makes a compelling argument for NAS because most NAS solutions are tuned for high volumes of users and files on a given share as opposed to most typical Windows file server installations, which are out-of-the box installs with little to no performance-tuning considerations.
If there are remote offices with an aging file server running in a closet and providing basic user home directory type services, this also could be a strong argument for migrating to a centrally located NAS appliance. On the other hand, if the organization consists of one location with a large community of remote users connecting to the file shares through VPN or other access gateways, the NAS option has less appeal, as the cost associated with NAS wouldn't be outstripped by the benefits to the remote users (performance benefits will be lost across the intervening networks). If the infrastructure includes Unix or Linux servers that require access to the same file storage as the Windows servers, a NAS appliance can provide seamless integration of file services between the operating systems if implemented properly. For instance, if the user community is prone to requesting file restores or other data recovery on a frequent basis, having snapshots available on disk from last night or last week can save hours of administration time recalling tapes and performing lengthy restores.
Key questions to ask network-attached storage vendors
Besides asking questions relating to the internal environment of the organization, SMBs must also ask questions to potential NAS vendors. Key questions include things like what are the maximums? For most SMBs this will not be an issue, but if, for example, the planned utilization for the NAS includes some sort of support for storing third-party client files or e-discovery data, the maximum number of files supported could easily become an issue if not known and planned for. If the solution being considered is of the NAS gateway variety, the question of what type of backend storage is supported must be asked.
Another question to ask to gateway vendors is do the storage vendors provide certification with the NAS gateway and how are compatibility and support issues resolved if there is an issue with the gateway?
Also, SMBs should ask supportability questions such as: Is the NAS certified by the operating systems and applications in use by the organization? Also, how do firmware updates apply to the NAS? And how mature are the products the vendor is offering? If a vendor is applying fixes to or releasing new versions of their core NAS software on a monthly (sometimes even weekly) basis, this should be a warning sign that the vendor has an immature product and should probably not be at the top of the list. Although this isn't a complete list, it should get the conversation with the potential vendors steered in the right direction.
Network-attached storage appliances may not be the best alternative for a given SMB; there is nothing wrong with maintaining Windows or Unix file servers. But, if the questions above are answered clearly and thoughtfully by the business and the vendors, NAS can help reduce costs and some of the headaches for small IT departments by replacing disparate stovepipe servers that have limited storage with extensible, shared storage pools on a NAS cluster and by consolidating heterogeneous file services and technology onto a homogenized, easy-to-manage platform.
About this author: Ron Scruggs has more than 17 years experience as a senior level engineer and consultant in storage, backup and server management. He has been an integral part of enterprise level storage, backup and recovery deployments for the past 10 years in multiple industries including government, financial, medical and IT service providers. Ron is currently serving as a senior consultant for GlassHouse Technologies in Framingham, MA, and is providing data protection architecture services in the Boston area.
This was first published in February 2010