Raid is what you use to kill bugs in your apartment right? Well, yes, it is that, but in computer speak it also is short for redundant array of independent disks – RAID. And what it is, is a technology that is used to store files by using a number of disk drives. You may have heard terms like sata raid storage system or raid level. This is how the data is referred to. Raid has become an all-encompassing term for a number of data storage systems that divide and replicate data among different disk drives. The different drives are often said to be “in raid”. One operating system is used as a single drive and then the different disks, depending on the raid level, are accessed through the operating system. The overall goal of raid is not just to provide additional storage performance, but also to ensure security in the data.
There are six common raid levels known as raid 0, raid 1, raid 2 and on and on up to raid 6. Each of these raid levels are built on top of each other and uses a process known as disk striping, this cordons off each of the drive’s storage space into different areas. Typically, these areas range anywhere from 512 bytes of storage all the way up to several megabytes. The stripes overlap to create a system in which the optimal amount of data can be saved but also to reduce disk failure.
Sata raid storage systems are sold by using a variety of descriptors like the number of drives, the number of terabytes, or TB, of storage as well as other terms like the amount of sata raid array in each device. In addition to raid systems, a second type of system is used to back up data and this is typically known as secondary storage. While raid is most often responsible for preventing against overwhelming data loss due to failure of one drive, or in the case of raid 6, two drives the backup system is different. A real backup system does not just include raid but additional elements like the ability to recall and bring back previous versions of data. This helps to save against the loss of software errors but also for recovery in the case of malware.
In addition to physical disks that can include raid, it can also be provided by an operating system by way of virtualization or through a virtual device. Typically, raid that is implemented as software work like a layer between multiple devices. In other instances there is something known as a volume manager which allows for different volumes to be moved or resized. And other times, operating systems provide the basic functions of raid without volume management. An example of one such operating system is Apple’s Mac OS X Server and Max OS X.
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