UNI IT Solutions partners with the organizations to deliver storage solutions which include all 3 format of storage:

  • DAS (Direct Access Storage)
  • SAN (Storage Area Network)
  • NAS (Network-Attached Storage)
  • Hybrid (SAN-NAS)

DAS (Direct Access Storage): It refers to a data storage devices directly attached to a server or workstation, without a storage network in between. It is a retronym, mainly used to differentiate non-networked storage from SAN & NAS.

A typical DAS system is made of a data storage device (for example enclosures holding a number of hard disk devices) connected directly to a computer through a host bus adopter (HBA). Between those two points there is no network device (like hub, switch, or router), and this is the main characteristic of DAS.

The main protocol used for DAS connections are ATA, SATA, eSATA, SCSI, SAS, and Fiber Channel.

SAN (Storage Area Network): It is a file-level computer data storage connected to a computer Network providing data access to heterogeneous clients. NAS not only operates as a file server, but is specialized for this task either by its hardware, software, or configuration of those elements. NAS is often made as a computer appliance – a specialized computer built from the ground up for storing and serving files – rather than simply a general purpose computer being used for the role.

NAS devices are gaining popularity, as a convenient method of sharing files among multiple computers. Potential benefits of network-attached storage, compared to file servers, include faster data access, easier administration, and simple configuration.

NAS systems are networked appliances which contain one or more hard drives, often arranged into logical, redundant storage containers or RAID arrays. Network-attached storage removes the responsibility of file serving from other servers on the network. They typically provide access to files using network file sharing protocols such as N/W File System Protocol (NFS), Server Message Block (SMB)/CIFS or Apple File Protocol (AFP).

A NAS unit is a computer connected to a network that only provides file-based data storage services to other devices on the network. Although it may technically be possible to run other software on a NAS unit, it is not designed to be a general purpose server. For example, NAS units usually do not have a keyboard or display, and are controlled and configured over the network, often using a browser.

SAN (Storage Area Network): It is a dedicated storage network that provides access to consolidated, block level storage. SANs primarily are used to make storage devices (such as disk arrays, tape libraries, and optical Jukeboxes) accessible to servers so that the devices appear as locally attached to the OS. A SAN typically has its own network of storage devices that are generally not accessible through the regular network by regular devices.

A SAN alone does not provide the “file” abstraction, only block-level operations. However, file systems built on top of SANs do provide this abstraction, and are known as SAN file systems or Shared disk file systems.

A Typical Storage in an organization is given below:

Typical Storage

Hybrid (SAN-NAS): SAN and NAS are not mutually exclusive, and may be combined as a SAN-NAS Hybrid, offering both file-level protocols (NAS) and block-level protocols (SAN) from the same system. An example of this is Open filer, a free software product running on Linux based systems.

Hybrid SAN-NAS