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data experiences the most wear and may need occasional replacement, but the tapes themselves can last for years to decades. If there are sealable access doors between the access mechanism and the media, it is possible for the idle media storage enclosure to survive fire, floods, lightning strikes, and other disasters.
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By comparison, standard hard drives are assumed to only be in operation for a few hours each day, and are not spinning when the computer is either turned off or in sleep mode. Standard hard drives may also use data caching methods that can improve single-drive performance, but would interfere with
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Some hard drive and storage systems vendors and suppliers use the term in reference to low-rotational speed hard drives that are built to be more reliable than generic desktop and laptop computer hard drives. They are intended to be operational continuously for 24 hours a day, seven days a week,
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Nearline tape and optical storage has the advantage of relatively longer lifespans compared to spinning hard drives, simply due to the storage media being idle and usually stored in protected dust-free enclosures when not in use. In a robotic tape loading system, the tape drive used for accessing
148:, with most drives in a MAID usually stopped. The MAID system spins up each drive on demand when necessary to read (or in some cases to write) data on that drive. For a given amount of storage capacity, MAID systems have higher densities and
83:), are nearline storage. Removable media such as tape cartridges that can be automatically loaded, as in tape libraries, are nearline storage, while tape cartridges that must be manually loaded are offline storage.
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The nearline storage system knows on which volume (cartridge) the data resides, and usually asks a robot to retrieve it from this physical location (usually: a
163:(NAS) systems, or as non-critical moderate-performance data storage on servers, where greater durability is required for the drive to operate continuously.
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99:, with tape cartridges placed on shelves in the front, and a robotic arm moving in the back. Visible height of the library is about 180 cm.
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storage") is a term used in computer science to describe an intermediate type of data storage that represents a compromise between
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are online storage, while spinning drives that spin down automatically, such as in
Massive Arrays of Idle Disks (
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storage devices. Presumably this usage is by analogy to the high-capacity and low-access speed tape systems.
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Nearline storage is not immediately available, but can be made online quickly without human intervention.
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requirements than "hot" storage systems that keep all the disks spinning at full speed at all times.
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Offline storage is not immediately available, and requires some human intervention to become online.
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42:/archiving (used for backups or long-term storage, with infrequent access to data).
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The formal distinction between online, nearline, and offline storage is:
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Inmon, W. H. (2005-10-07). "Chapter 2: The Data
Warehouse Environment".
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144:(massive array of idle drives) systems archive data in an array of
123:. This process is not instant, but it only requires a few seconds.
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244:"Survey of Near-Line Storage Technologies: Devices and Systems"
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Nearline hard drives may be used in personal or small business
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Online storage is immediately available for input/output (I/O).
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storage systems, potentially causing data loss or corruption.
38:(supporting frequent, very rapid access to data) and
119:to enable access by bringing the data it contains
242:Venkatramani, Chitra and Tzi-cker Chiueh (1993).
231:"A Glossary of Archival and Records Terminology"
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246:. Experimental Computer Systems Laboratory.
204:Building the Data Warehouse, Fourth Edition
267:IBM Developerworks, Inside System Storage
300:Seagate Technology Paper TP-543 (2005),
178:is being used to refer to high-capacity
137:Non-RAID drive architectures § MAID
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45:Nearline storage dates back to the
263:"Correct use of the term Nearline"
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206:. Whiley publishing. p. 33.
131:Hard disk drive nearline storage
75:For example, always-on spinning
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167:the operation of multi-drive
156:possibly for several years.
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303:. Retrieved on 2012-08-28.
233:. Retrieved on 2009-01-30.
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49:Mass Storage System (MSS)
291:Wednesday, 12 June 2019
161:network-attached storage
87:Robotic nearline storage
287:"Hanel storage systems"
150:lower power and cooling
261:Pearson, Tony (2010).
182:drives that work with
174:Specifically the term
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319:Computer data storage
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184:Serial Attached SCSI
111:) and put it into a
16:Type of data storage
176:nearline hard drive
227:"Nearline storage"
117:optical disc drive
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105:tape library
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51:tape library
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24:portmanteau
272:2015-08-16
190:References
180:Serial ATA
113:tape drive
313:Category
95:A large
57:Overview
30:" and "
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121:online
32:online
208:ISBN
169:RAID
142:MAID
81:MAID
28:near
26:of "
229:in
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22:(a
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