What is RAID?
Hard drives in our computer play a very important role. All information is stored on them. I do not want to lose everything overnight due to the failure of the hard. And they, as you know, also have their time limit for failure. Surely, many of you have heard of some RAID-arrays. Do them to speed up your computer and for data security. Let's talk more about this.
What is RAID, and what is it for?
RAID - a disk array of multiple hard drives. In practice, a RAID array is a system consisting of two hard disks connected to the motherboard, supporting the possibility of creating arrays (or to a raid controller). What is a RAID controller? A device that manages your array and related work processes. Usually they are used on server machines. Such a toy is of little use to ordinary users - it is not cheap and inefficient, considering the amount of information processed by an ordinary computer. When creating a RAID-array hardware stuffing your computer will not change. Programmatically, all work with the raid is carried out in bios, that is, nothing laborious.
SCSI RAID: Unlike Classic Array
SCSI is an interface, a physical type of device connection. It differs from the usual IDE or SATA interfaces, first of all, by a different algorithm of operation, which provides a higher speed and is too high, relative to the latter, by the price. Received on large-scale server machines, among ordinary computers rarely installed.
- We find a motherboard with support for raid arrays or SCSI RAID.
- We take two identical disks, we connect.
- We go in bios (depends on the model of the motherboard.).
- Parameter SATA Configuration, we expose RAID.
- During the boot process, press Ctrl + I.
- We configure raid.
Done! Important: when creating RAIDs, all information from the disks is deleted!
Types of arrays
- RAID 0 is a disk array for improved performance.
- RAID 1 is a “mirrored” disk array.
- RAID 2 - arrays that use Hamming code.
- RAID 3 and 4 are interleaved disk arrays with a dedicated parity disk.
- RAID 5 - interleaved and unallocated parity disks.
- RAID 6 - interleaved disks with 2 independent parities.
- There are still raids 10, 50, 60. But these are too complex structures.
More details on the two most popular versions of raid arrays. These are, respectively, RAID 0 and RAID 1. What is RAID 0 for? It's not that hard.The principle of the array is the parallel operation of different physical devices, issued by the system for one. That is, it directly increases the speed of the system, just imagine: two disks participate in your raid 0 array. You are recording data of 10 gigabytes. If you did not create an array, you would have to write them to a specific disk, while the second one would be idle. In the case of a raid 0 array, your data is divided into several streams byte-by-byte, and is also recorded on the media randomly. That is, one film can be stored on two physical devices at the same time, and on one there will be only 30% of its “weight”. Minus RAID 0 in the absence of fault tolerance. Moreover, if one disk fails, you will not be able to recover data from the second one either.
Now let's talk about RAID 1. In the case of this array, you will have to use several additional disks for "mirroring". If you have only two disks in the array, then it looks like this: you are working with disk number 1, and the computer duplicates all your actions for disk 2. In the event of a device failure, all your data will be safe and sound on the duplicate disk. Safe, sure. The disadvantage of raid 1 can be called a loss of performance.
What you need a RAID array, you now know, it remains only to determine what suits you best. Data integrity or performance boost? Everyone's personal matter!