There is often confusion surrounding the difference between G-Drives and G-Raids and the various different RAID settings so I've done up this blog to try answer a few of those questions. If you've any further questions just drop us a line!
The G-DRIVE is a single drive product, while the G-RAID contains two internal drives. The benefit of a single drive unit is it’s smaller size and reduced heat, so no fan is required. The G-RAID uses two drives hardwired as Raid 0 (Striped) so the computer will see the unit as a single larger drive. The paired drives can increase performance up to 50% over a single drive unit. This increase varies based on connection type and the system’s capabilities.
G-RAID Minis can also be formatted to a RAID 1 (Mirrored) configuration and G-Speed & G-Raid Studio models can be set to various other RAID configurations depending on the spec. Standard G-Raid Desktop models can only be used as RAID 0.
RAID (Redundant Array of Independent Disks) is a data storage technology that combines multiple disk drive components into a logical unit for the purposes of data redundancy and / or performance improvement. Data is distributed across the drives in one of several ways, referred to as RAID levels, depending on the specific level of redundancy and performance required.
RAID involves computer data storage schemes that can divide and replicate data among multiple physical drives and is an example of storage virtualization whereby the array can be accessed by the operating system as one single drive. The different schemes or architectures are named by the word RAID followed by a number (e.g. RAID 0, RAID 1). Each scheme provides a different balance between the key goals: reliability and availability, performance and capacity. RAID levels greater than RAID 0 provide protection against unrecoverable (sector) read errors, as well as whole disk failure.
RAID 0 (standard shipping setting on all G-Raids / G-Speeds)
RAID 0 comprises 2 or more internal drives splitting the data between them to increase speed and performance. This level provides no data redundancy nor fault tolerance, but improves performance through parallelism of read and write operations across multiple drives. RAID 0 has no error detection mechanism, so the failure of one disk causes the loss of all data on the array.
RAID 1 (G-Raid Minis, G-Raid Studios and G-Speeds can be set to this)
RAID 1 comprises mirroring (without parity or striping). Data is written identically to two (or more) internal drives, thereby producing a "mirrored set". Write performance can be degraded because all drives must be updated simultaneously. Maximum storage capacity will also be halved (e.g. a 2TB G-Raid Mini will only be able to hold 1TB of data if set to RAID 1 because all the data is mirrored on both internal drives).
RAID 5 (G-Speed models can be set to this)
RAID 5 is for RAID configurations with 3 or more internal drives and comprises block-level striping with distributed parity information distributed among the drives. It requires that all drives but one be present to operate. Upon failure of a single drive, subsequent reads can be calculated from the distributed parity such that no data is lost.
RAID 6 (G-Speed Studio models can be set to this)
RAID 6 is for RAID configurations with 3 or more internal drives and comprises block-level striping with double distributed parity. Double parity provides fault tolerance up to two failed drives. This makes larger RAID groups more practical, especially for high-availability systems, as large-capacity drives take longer to restore. As with RAID 5, a single drive failure results in reduced performance of the entire array until the failed drive has been replaced.
RAID 10 (G-Speed Studio models can be set to this)
RAID 10 is for RAID configurations with 3 or more internal drives and comprises a mirror of striped drive pairs resulting in higher performance than RAID 1 but with the same level of data protection. As with RAID 1, useable storage space is 50% of total available capacity.
JBOD (G-Raid Studio models can be set to this)
JBOD denotes ‘Just a Bunch Of Disks’ and means that each internal drive can be accessed as an individual hard drive. When your G-Raid Studio is set to this configuration there is no mirroring or increase in performance as each internal drive is working independently.