RAID (Redundant Array of Independent Disks) is a technology that allows multiple physical disks to be combined into a single logical unit for better performance, reliability, and capacity. RAID can be implemented in hardware or software.
There are different RAID levels, each with its own pros and cons. The most common RAID levels are:
- RAID 0: Also known as striping, RAID 0 splits the data evenly across two or more disks, improving performance by allowing data to be read and written in parallel. However, RAID 0 does not provide any redundancy, meaning that if one disk fails, all data is lost.
- RAID 1: Also known as mirroring, RAID 1 duplicates data across two or more disks, providing redundancy. If one disk fails, data can still be retrieved from the other disk(s). RAID 1 provides good data protection, but at the cost of reduced capacity and no performance gains.
- RAID 5: RAID 5 distributes data and parity across three or more disks, providing both performance improvements and redundancy. If one disk fails, the parity information can be used to reconstruct the lost data. However, RAID 5 can be slow for write-intensive workloads.
- RAID 6: RAID 6 is similar to RAID 5, but with an additional parity block for greater redundancy. RAID 6 can survive the failure of two disks, making it more reliable than RAID 5. However, it has a higher overhead and can be slower for write-intensive workloads.
- RAID 10: RAID 10 combines the benefits of RAID 0 and RAID 1. It uses four or more disks to create two RAID 1 arrays, and then combines them into a single RAID 0 array. RAID 10 provides both performance improvements and redundancy, making it a popular choice for high-performance applications.
RAID is widely used in enterprise-level storage systems, such as data centers and servers. It can also be used in desktop computers and laptops for better performance and data protection.