Raidéjärjestelmät

Raidéjärjestelmät, often translated as "raiding systems" or "raid configurations," refers to data storage solutions that combine multiple physical disk drives into one or more logical units for the purposes of data redundancy, performance improvement, or both. The primary goal of RAID is to protect data from drive failure and/or to increase the speed at which data can be read from or written to the storage. Different RAID levels offer varying balances between these two objectives.

Common RAID levels include RAID 0, RAID 1, RAID 5, and RAID 6. RAID 0, also known as striping, distributes data across multiple drives without any redundancy. This offers the highest performance but provides no protection against drive failure; if one drive fails, all data is lost. RAID 1, or mirroring, writes identical data to two or more drives, providing excellent redundancy. If one drive fails, the data can be accessed from the remaining drive(s). However, it has a lower storage efficiency as half the capacity is used for mirroring.

RAID 5 uses block-level striping with distributed parity. It requires at least three drives and offers a good balance of performance, storage efficiency, and redundancy. Parity information is spread across all drives, allowing the system to reconstruct data if one drive fails. RAID 6 is similar to RAID 5 but adds a second, independent parity block, allowing it to withstand the failure of two drives simultaneously. This provides higher reliability but at a slight performance and capacity cost compared to RAID 5. The choice of RAID level depends on the specific needs for data protection, performance, and budget.