If you are given the option whether to make use of the Network Attached Storage (NAS) or direct-attached storage (DAS) for your storage needs? What would be your choice? Although there isn’t an answer that applies for every circumstance as each company has its own requirements, these are five reasons an organization may opt for enterprise NAS instead of DAS.
DAS is limited in storage capacity
One of the primary reasons some companies choose the best NAS systems instead of DAS is because DAS is a storage system with limited capacity. As its name suggests, DAS is directly connected with the server. The issue is that the server can support only limited number of disks.
The NAS devices on the other do have a limit on the number of disks they can physically hold. However, NAS storage generally has better scalability than DAS. Thus, while smaller NAS appliances might only support a handful of disks, a huge NAS storage cluster may accommodate virtually unlimited number of drives.
NAS has a Flexible architecture
We are talking about RAID and tiered storage here. NAS appliances generally offer a versatile storage architecture. If enough disks are available, you can configure DAS to make use of one or more types of RAID, or, in certain instances, you can configure tiered storage.
However, most of the time, Network Attached Storage provides more choices. For example, NAS appliances may support certain more sophisticated RAID levels which aren’t typically available in DAS. Additionally, certain NAS storage vendors permit several NAS devices to be connected in a cluster to provide a high degree of scalability, which is not possible with DAS.
NAS is better suited for shared storage
DAS storage is shared with other systems, however, just at the OS level.
However, NAS storage can also be accessed without an operating system on the remote server. A NAS appliance is equipped with its own OS; a smaller, lighter specially-designed Linux kernel made to be reliable and stable.
Since DAS is usually shared at the file level, it’s not suitable for creating storage in clusters. However, the higher-end NAS appliances easily connect with each other. This makes them appropriate for use as clustered storage.
It is easier to set up.
It is more straightforward to set up NAS as opposed to DAS. Almost all storage providers often incorporate wizards that guide administrators through the first configuration procedures within a couple of seconds. If you compare that to DAS, it is directly connected to the server, and administrators must be aware of the intricacies of such storage. They must know how to connect the storage on the hardware level and how the server OS manages the storage.
NAS offers easy Redundancy
NAS storage appliances can offer a higher degree of redundant drives, which is especially true for higher-end models. Certain NAS appliances also have an alternate power supply. Many NAS appliances like StoneFly’s super scale-out NAS also have built-in replication mechanisms that permit the contents of the appliance to be replicated onto a second NAS appliance to guard against any failure.
Bottom Line
It is theoretically possible to attain similar redundancy levels and share storage by using DAS; however, it requires technical expertise and a deeper understanding of the operating system for servers and the hardware. Therefore, for organizations wanting a cost-effective and quick setup, NAS storage is much more suitable.