RAID Levels

RAID Levels
RAID 5:-  RAID 5 will provide good performance throughput and prevent data loss if there is a disk failure. For the database which has high read/write activity, RAID 5 will be a better choice when compared to RAID 0 and RAID 1 in terms of data availability and data protection. For an ideal SQL Server configuration, you should have a combination of RAID 1 and RAID 5. You should mirror the operating system using RAID 1, and place transaction logs on a RAID 1 that is separate from the RAID 1 that hosts the operating system. SQL Server writes data to the transaction logs and maintains serial information of all modifications that occurred in a SQL database. The transaction log files can be used for rollback and roll forward of information from a SQL Server database. The SQL Server files and filegroups should be placed on a RAID 5, because you get best performance throughput by placing database files on RAID 5 disk array.

RAID 10 RAID 10 is a better choice than RAID 5, but RAID 10 would be more expensive than RAID 5. RAID 10 is a combination of RAID 0+1, which is known as striping with mirroring. You should first mirror disks and then create a stripe set of mirrored disks. This provides high fault tolerance for data and excellent throughput performance.

RAID 1 RAID 1 is known as disk mirroring. You need a minimum of two disks to form a RAID 1 array. One primary disk is used for read/write operations and the data is replicated to the second disk. This RAID level offers better read performance but slower write performance.

RAID 0 RAID 0 is known as disk striping. This RAID level stripes data across disks in the array, offering better throughput on the read/write operations. However, there is no data protection offered in this RAID level. If one disk fails, the data stored on the disk will be lost.