Disk Array

What Does Disk Array Mean?

A disk array is a data storage system that contains multiple disk drives and a cache memory. It efficiently distributes data across multiple drives and enables fault tolerance through redundant array of independent disks (RAID). Some disk arrays also use virtualization, which provides additional functionality by optimizing storage use and providing greater flexibility for users managing stored data.


Techopedia Explains Disk Array

A typical disk array includes cache memory, special controllers, disk enclosures and a power supply. These components are often hot-swappable, which means they can be disconnected and reconnected without shutting the system down. Disk arrays provide many advantages in data availability, resiliency through redundant components and ease of maintenance.

Categories of disk arrays include:

  • Network attached storage (NAS) arrays
  • Storage area network (SAN) arrays (modular SAN, monolithic SAN and utility storage arrays)
  • Storage virtualization

An NAS system is a network of appliances that contains several hard drives arranged into RAID arrays. It relieves the file-serving function of file servers, providing both storage and a file system. SAN only provides block-base storage, leaving the file system to network client machines. However, the two may be combined into an SAN/NAS hybrid, offering both protocols for block-base storage and file storage on the same system.


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Margaret Rouse
Technology Expert

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.