Technical Definition of RAID 1
- Raid level 1 provides redundancy by writing all data to two are more drives. The performance of level 1 array tends to be faster on reads and slower on writes compared to a single drive but if other drives fails no data is lost. This is good entry level redundant system, since only two drives are regained ; however, since one drive is used to store a duplicate of the data, the cost per megabyte is high. This level is commonly referred to as mirroring.
- Disk mirroring, also known as RAID 1, is the replication of data to two or more disks. Disk mirroring is a good choice for applications that require high performance and high availability such as transactional applications, email, and operating systems. Because both disks are operational, data can be read from them simultaneously, which makes read operations quite fast. Write operations, however, are slower because every write operation is done twice.
- This type is also known as disk mirroring and consists of at least two drives that duplicate the storage of data. There is no striping. Read performance is improved since either disk can be read at the same time. Write performance is the same as for single disk storage. RAID-1 provides the best performance and the best fault-tolerance in a multi-user system.
