DAS versus NAS
DAS offers direct, cost-effective storage, ideal for individual use, while NAS provides shared, scalable storage, suitable for collaborative environments.
With data, the lifeblood of businesses, even small- and medium-sized enterprises need to store terabytes and often petabytes of data.
Storage-area networks (SANs) offer immense storage capacities but are complex and expensive to deploy and maintain. Generally, the largest enterprises have the need and wherewithal to implement them.
The practical storage options for most small- and medium-sized businesses (SMBs) continue to be direct-attached storage (DAS) and network-attached storage (NAS).
DAS remains the simplest and least expensive storage strategy. One or more hard drives—spinning disks, solid-state drives, or optical drives—are directly connected to a computer exclusively for its use.
While this one-to-one relationship imposes limitations, it also offers advantages. Without having to traverse a network, reads and writes can occur at the maximum speeds the technology allows. DAS is also simpler and doesn’t require the switches, routers, etc. of a network, making it the least expensive computer/storage configuration.
Moreover, DAS solutions are scalable. DAS RAID arrays can scale to petabytes while providing strong data protection. Many of these systems can expand even further by attaching JBODs (Just a Bunch of Drives) to them.
Data, files, and other resources, however, often need to be shared by users and servers. In such circumstances, NAS is the solution. With NAS, a storage platform is connected to the enterprise network where it is accessible to multiple users. Users and servers can access the resources on the platform whether they are across a campus or across a continent.
NAS solutions also offer security precautions. For example, users across the enterprise can be segmented into zones. Even if an intruder manages to penetrate the network through the front door, they will be unable to access servers with sensitive data tucked away into zones. Only the CFO and designated employees, for example, will have access to the server with the company’s financial records.
NAS systems are good for unstructured files, which are the majority of digital resources circulating around most enterprise networks. SANs are good for the structured records of enterprise-level databases.
But it’s not necessarily an either-or choice these days. There are storage providers that offer combined NAS and SANs in a single unified storage system.
Moreover, today’s advanced NAS systems offer extraordinary scalability. Like DAS, JBODs can be connected to a NAS platform for greater storage capacity. JBODs, however, lack controllers, so the only controllers will be those in the original platform. This contains the costs of JBODs but makes them good for warm or cold storage that isn’t accessed all that often.
Instead, NAS solutions can use management software to federate storage systems into a unified storage pool. Called scale-out NAS, multiple devices can be consolidated into a single, distributed storage system. Files are easily accessed regardless of their physical location and storage can be increased by adding more drives or even entire arrays. The addition of more CPUs and RAM increases performance.
Even better, the storage components can be commodity products, making scale-out NAS a cost-effective approach for meeting strong or unpredictable data growth. SMBs have a variety of cost-effective, function-rich NAS strategies to choose from.
