RAID 1E, also known as hybrid mirroring, striped mirroring and enhanced mirroring, is a type of nested RAID level that uses two-way mirroring on a minimum of two disks.
In other words, RAID 1E combines RAID 0 with RAID 1. Data stripe is the first stripe, and the second is the mirror of the first data stripe shifted one drive. It is called mirrored stripe because a complete stripe of data is copied to another stripe within the set of disks. RAID 1E provides better performance and drive redundancy than RAID 1.
Formulation of RAID 1E requires at least three drives, and can support up to maximum of 16 drives. RAID 1E only allows one-half of the capacity of the array to be used. In the event of failure of any of the drives, the read / write operations are transferred to other operational drives within the array.