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A disk array is a
disk storage
Disk storage (also sometimes called drive storage) is a general category of storage mechanisms where data is recorded by various electronic, magnetic, optical, or mechanical changes to a surface layer of one or more rotating disks. A disk drive is ...
system which contains multiple disk drives.
It is differentiated from a
disk enclosure
A disk enclosure is a specialized casing designed to hold and power disk drives while providing a mechanism to allow them to communicate to one or more separate computers.
Drive enclosures provide power to the drives therein and convert the dat ...
, in that an array has
cache
Cache, caching, or caché may refer to:
Places United States
* Cache, Idaho, an unincorporated community
* Cache, Illinois, an unincorporated community
* Cache, Oklahoma, a city in Comanche County
* Cache, Utah, Cache County, Utah
* Cache County ...
memory and advanced functionality, like
RAID
Raid, RAID or Raids may refer to:
Attack
* Raid (military), a sudden attack behind the enemy's lines without the intention of holding ground
* Corporate raid, a type of hostile takeover in business
* Panty raid, a prankish raid by male college ...
,
deduplication,
encryption
In cryptography, encryption is the process of encoding information. This process converts the original representation of the information, known as plaintext, into an alternative form known as ciphertext. Ideally, only authorized parties can decip ...
and
virtualization
In computing, virtualization or virtualisation (sometimes abbreviated v12n, a numeronym) is the act of creating a virtual (rather than actual) version of something at the same abstraction level, including virtual computer hardware platforms, stor ...
.
Components of a disk array include:
*
Disk array controller
A disk array controller is a device that manages the physical disk drives and presents them to the computer as logical units. It almost always implements hardware RAID, thus it is sometimes referred to as RAID controller. It also often provides ...
s
*
Cache
Cache, caching, or caché may refer to:
Places United States
* Cache, Idaho, an unincorporated community
* Cache, Illinois, an unincorporated community
* Cache, Oklahoma, a city in Comanche County
* Cache, Utah, Cache County, Utah
* Cache County ...
in form of both volatile
random-access memory
Random-access memory (RAM; ) is a form of computer memory that can be read and changed in any order, typically used to store working Data (computing), data and machine code. A Random access, random-access memory device allows data items to b ...
and
non-volatile flash memory
Flash memory is an electronic non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for the NOR and NAND logic gates. Both us ...
.
*
Disk enclosure
A disk enclosure is a specialized casing designed to hold and power disk drives while providing a mechanism to allow them to communicate to one or more separate computers.
Drive enclosures provide power to the drives therein and convert the dat ...
s for both
magnetic
Magnetism is the class of physical attributes that are mediated by a magnetic field, which refers to the capacity to induce attractive and repulsive phenomena in other entities. Electric currents and the magnetic moments of elementary particle ...
rotational
hard disk drive
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnet ...
s and electronic
solid-state drive
A solid-state drive (SSD) is a solid-state storage device that uses integrated circuit assemblies to store data persistently, typically using flash memory, and functioning as secondary storage in the hierarchy of computer storage. It is ...
s.
*
Power supplies
A power supply is an electrical device that supplies electric power to an electrical load. The main purpose of a power supply is to convert electric current from a source to the correct voltage, current, and frequency to power the load. As a res ...
Typically a disk array provides increased availability, resiliency, and maintainability by using additional redundant components (controllers, power supplies, fans, etc.), often up to the point where all
single points of failure (SPOFs) are eliminated from the design.
Additionally, disk array components are often
hot-swappable
Hot swapping is the replacement or addition of components to a Computer, computer system without stopping, shutdown (computing), shutting down, or Reboot, rebooting the system; hot plugging describes the addition of components only. Components ...
.
Traditionally disk arrays were divided into categories:
*
Network attached storage
Network-attached storage (NAS) is a file-level (as opposed to block-level storage) computer data storage server connected to a computer network providing data access to a heterogeneous group of clients. The term "NAS" can refer to both the techn ...
(NAS) arrays
*
Storage area network
A storage area network (SAN) or storage network is a computer network which provides access to consolidated, block-level data storage. SANs are primarily used to access data storage devices, such as disk arrays and tape libraries from serve ...
(SAN) arrays:
** Modular SAN arrays
** Monolithic SAN arrays
** Utility Storage Arrays
*
Storage virtualization
In computer science, storage virtualization is "the process of presenting a logical view of the physical storage resources to" a host computer system, "treating all storage media (hard disk, optical disk, tape, etc.) in the enterprise as a singl ...
Primary vendors of storage systems include
Coraid, Inc.,
DataDirect Networks
DataDirect Networks (DDN) is a privately-held data storage company, and is headquartered in Chatsworth, California, USA. Summary
DDN provides storage systems for unstructured data and big data, like AI, analytics and high performance computi ...
,
Dell EMC
Dell EMC (EMC Corporation until 2016) is an American multinational corporation headquartered in Hopkinton, Massachusetts and Round Rock, Texas, United States. Dell EMC sells data storage, information security, virtualization, analytics, cloud c ...
,
Fujitsu
is a Japanese multinational information and communications technology equipment and services corporation, established in 1935 and headquartered in Tokyo. Fujitsu is the world's sixth-largest IT services provider by annual revenue, and the la ...
,
Hewlett Packard Enterprise
The Hewlett Packard Enterprise Company (HPE) is an American multinational information technology company based in Spring, Texas, United States.
HPE was founded on November 1, 2015, in Palo Alto, California, as part of the splitting of the H ...
,
Hitachi Data Systems
Hitachi Data Systems (HDS) was a provider of modular mid-range and high-end computer data storage systems, software and services. Its operations are now a part of Hitachi Vantara.
It was a wholly owned subsidiary of Hitachi Ltd. and part of th ...
,
Huawei
Huawei Technologies Co., Ltd. ( ; ) is a Chinese multinational technology corporation headquartered in Shenzhen, Guangdong, China. It designs, develops, produces and sells telecommunications equipment, consumer electronics and various smar ...
,
IBM,
Infortrend
Infortrend Technology () is a Taiwanese technology company specializing in SAN and NAS storage systems. The company is headquartered in the Zhonghe District of New Taipei, Taiwan, and has regional headquarters in Tokyo, Sunnyvale, California, Be ...
,
NetApp
NetApp, Inc. is an American hybrid cloud data services and data management company headquartered in San Jose, California. It has ranked in the Fortune 500 from 2012–2021. Founded in 1992 with an IPO in 1995, NetApp offers cloud data services ...
,
Oracle Corporation
Oracle Corporation is an American multinational computer technology corporation headquartered in Austin, Texas. In 2020, Oracle was the third-largest software company in the world by revenue and market capitalization. The company sells da ...
,
Panasas
Panasas is a data storage company that creates network-attached storage for technical computing environments.
History
Panasas is a computer data storage product company and is headquartered in San Jose, California. Panasas received seed funding ...
,
Pure Storage
Pure Storage is an American publicly traded technology company headquartered in Mountain View, California, United States. It develops all-flash data storage hardware and software products. Pure Storage was founded in 2009 and developed its product ...
and other companies that often act as
OEM
An original equipment manufacturer (OEM) is generally perceived as a company that produces non-aftermarket parts and equipment that may be marketed by another manufacturer. It is a common industry term recognized and used by many professional or ...
for the above vendors and do not themselves market the storage components they manufacture.
References
{{DEFAULTSORT:Disk array
Computer data storage
Fault-tolerant computer systems
RAID