Owner's manual
5
About the PortaGig 62 and Drive Modes
The PortaGig 62 enclosure contains two hard disk drives, which function as one single volume. Through the use of the Glyph
Manager software utility, it supports three drive modes: RAID 1 (mirroring), RAID 0 (striping), and Spanning. Each drive mode has
its own advantages, depending upon the application.
RAID 1 (mirroring) oers data redundancy and real-time backup by writing the same data to the two hard drives at the
same time. Should a drive failure happen, data is still available on the remaining drive. In RAID 1 mode, the two drives are
seen by the computer as one volume, but with half the capacity. For example, a 1TB PortaGig 62 will be seen as a 500GB
drive. Reading and writing occurs on both drives simultaneously so that each of the drives contains exactly the same
data, mirroring each other. If either of the drives should fail the other is there to continue to provide operation.
RAID 0 (striping) increases the performance of the drive system by spreading the data across two drives. RAID 0 is a
proven technology for editing video, working with huge graphics les, sound libraries, and streaming instruments that
play hundreds of samples simultaneously. RAID 0 is the default shipping drive mode. In RAID 0 (striping) mode, the two
drives are seen by the computer as one large drive, and reading and writing occurs on both drives simultaneously. It is
designed to increase the performance and data throughput of the drive system. The PortaGig 62’s built-in RAID controller
splits each piece of data across both of the drives in segments and distributes the I/O burden. Since data is written with-
out any form of parity data-checking, it allows for the fastest data transfer of all other RAID levels. However, if one drive
becomes damaged, the data on both drives can become corrupted. RAID 0 is not redundant or fault tolerant like RAID
levels 1, 3, and 5, but the trade o is that it’s the fastest of all RAID levels. MAKE SURE TO BACKUP YOUR DATA OFTEN!
In Spanning mode, the two drives are seen as one large drive and data is written sequentially across them. When the rst
drive lls to the limit, data is then written to the second drive. This mode is useful for applications requiring large vol-
umes, but not requiring the speed of RAID 0. Spanning does not provide any performance or redundancy benets.