RAID, which stands for Redundant Array of Independent Disks, is a technology used to combine multiple physical hard drives into a single logical unit to improve performance, increase data redundancy, or both.
It’s commonly employed in servers to enhance reliability and efficiency
There are several RAID levels, each offering different benefits:
RAID 0 (Striping):
This level stripes data across multiple disks, improving performance. However, it provides no redundancy, meaning if one drive fails, all data is lost.
RAID 1 (Mirroring):
This level duplicates data across multiple disks, providing redundancy. If one disk fails, the system continues to operate using the mirrored copy.
RAID 5 (Striping with Parity):
This level distributes data and parity information across all disks. It offers a balance between performance, redundancy, and storage efficiency. If a single disk fails, data can be reconstructed using the parity information.
RAID 6 (Striping with Double Parity):
Similar to RAID 5 but with additional parity for extra fault tolerance. It can withstand the failure of two disks.
RAID 10 (1+0):
This level combines RAID 1 and RAID 0, offering both mirroring and striping. It provides high performance and redundancy but requires at least four disks.
Usage in Servers:
In servers, RAID is used to ensure data integrity, enhance performance, and provide fault tolerance. For instance:
Performance Improvement:
RAID 0 can boost read and write speeds by spreading data across multiple disks.
Redundancy:
RAID 1, 5, 6, and 10 protect against data loss due to hardware failure, making them ideal for critical applications where data availability is crucial.