User guide
OWC Mercury Rack Pro Chapter 1 - Introduction
RAID 1 “Drive Mirroring” Mode (2 drives installed only)
Switch setting: UP-UP-DOWN
The drives show up as one volume, but only 50% of the total capacity can be used. It is 
highly recommended to use identical drives for this RAID method. However, while you 
can utilize drives of dierent capacity, the RAID size will be based on the smallest ca-
pacity total of the drives used in the RAID set. RAID 1 creates an exact copy (or “mirror”) 
of a set of data on the second drive. This is useful when reliability and backup are more 
important than capacity. When one drive fails, it can be replaced and the data rebuilt.
RAID 10 “Drive Mirroring with Striping” Mode
Switch setting: UP-UP-DOWN
The drives show up as one volume, but only 50% of the total capacity can be used, 
depending on the drive with the smallest capacity. RAID 10 creates an exact copy (or 
“mirror”) of a set of data but also uses a RAID 0 Stripe for speed. When one drive fails, it 
can be replaced and the data rebuilt automatically.
RAID 3 “Drive Striping with Dedicated Parity” Mode
Switch setting: UP-DOWN-DOWN
The drives show up as one volume, but the total capacity, depending on the drive with 
the smallest capacity, is the combined size minus the size of one drive. RAID 3 uses 
byte level striping with parity data located on 1 drive. Very fast performance can be 
achieved with RAID 3 while also maintaining fault protection, so if one drive fails, it can 
be replaced and the data rebuilt automatically.
RAID 5 “Drive Striping with Distributed Parity” Mode
Switch setting: DOWN-UP-DOWN
The drives show up as one volume, but the total capacity, depending on the drive with 
the smallest capacity, is the combined size minus the size of one drive. RAID 5 uses 
block level striping with parity data distributed across all member disks and therefore 
provides the perfect balance between high performance and data integrity. When one 
drive fails, it can be replaced and the data rebuilt automatically.
Storage Capacity
Data Safety
Performance
Storage Capacity
Data Safety
Performance
Storage Capacity
Data Safety
Performance
Storage Capacity
Data Safety
Performance










