What is the Basic Difference between NAS and DAS?

Before assessing the difference between NAS and DAS, it is important to understand its fundamental characteristics and meaning. DAS stands for direct attached storage for a tape or disk (usually). A wire or cable directly attaches it to a computer processor. Your PC’s hard disc drive and tape drive complies with a single server. These are simple forms of DAS. The concerned I/O requests like commands or protocols have a direct access to these devices.

File area network
File area network (Photo credit: Wikipedia)

NAS stands for network attached storage. Its appliance device contains an integrated processor alongside disk storage. It is attached to the IP/TCP driven networks like WAN or LAN alongside accessed and specialized file sharing or file access protocols.

The file requests obtained by NAS get translated within the internal processor for the formatting requests.

The primary aspects

There are certain factors that the corporate world and its cohort IT services must consider while selecting storage solutions. These are overall usage, disk load, size requisites, recoverability and connectivity.

With reference to the topic, you do not have any cookie-cutter troubleshooting device for storage glitches. As regards the DAS directive, you will find it in environments where the device is knit with a lone physical server.

Mostly, it caters to a backup solution in bigger domains. For smaller companies, DAS might be the only storage solution for running the concerned workloads. This form of storage is physically compliant with one definite server since it is organically looped to that server. This is the only mode of maneuvering things before SANS hit the market. Since it is compliant with a server, you do not have a multiple server folds hitting it. In a way, it impedes you from obtaining the benefits of storage utilization, virtualization and disaster recovery.

The NAS inference

You will find that a network-attached storage primarily caters to the file-sharing storage. You will find other maneuvers like shared information files and network file systems in this juncture. Smaller organizations incorporate this mechanism for running a storage device. This helps in entering into a network-synced and enterprise-class storage with the concerned EMC.

The novel VNX storage units or platforms are a viable option since they contain block and file capabilities. The main outlook is its feasibility or utility in this network. If it is only for data files, the NAS directive is surely a good option.

The relative difference

As regards a direct-attach server, the storage hard drives are placed in the concerned sever. The SCSI commands percolate through the SCSI bus. In this way, an application that strives on server can gain high-speed accessibility to local storage. The prime disadvantages are:

  • Cannot percolate the capacity
  • You have no data sharing
  • There is no pervading drive virtualization within a single fold
  • You have to manage each server independently

Pertaining to the NAS fold, you locate the application to another server with IP connectivity for auxiliary storage devices. The main purpose is file sharing but you do have performance limitations in this regard. The primary difference DAS and NAS is that the former is a mere extension to an already existing server, which necessitates networking. NAS is crafted as a self-contained and easy solution for file-sharing within the network.

However, both can potentially increase data availability by incorporating clustering or RAID. Generally, NAS is not that customizable with reference to hardware like memory, CPU and storage components. The same applies to the software mold like plug-ins, extensions and additional protocols.