Massive Array of Idle Disk (MAID) is a storage concept for mass storage that is located between secondary storage for direct data storage and tertiary storage for data backup and archiving. From the name MAID it is clear that in the MAID concept there are hard disks that are in an idle state.
The MAID concept is a disk array. In contrast to the classic disk array, in the Massive Array of Idle Disk (MAID) only the hard disk on which data is written or from which data is read is in operation. All other hard disks are in idle mode, which contributes significantly to reducing power consumption and heat generation. This concept is therefore of particular interest in connection withGreen IT.
MAID arrays are designed for high storage capacities of several terabytes( TB) up to several hundred terabytes and consist of hundreds of hard disks. The MAID concept is somewhat similar to a large Just a Bunch Of Disks( JBOD) with power management. The MAID systems are switched like RAID systems for data redundancy, whereby the implementation is mostly according to RAID 5.