OWC Mercury Elite Pro Dual Assembly Manual & User Guide

MERCURY ELITE PRO DUAL
DEVICE SETUP
10
2.3.2 RAID Modes
Independent Drive Mode:
Each drive appeara as an individual disk in the OS. If you are using drives of
diering capacity or model, or for single drive setups, this is the best option.
NOTE: Due to the incomplete support in OS X for the chipsets used in the
Mercury Elite Pro Dual, independent drive mode has the following limitations:
1. When connected over Thunderbolt in OS X 10.8.3 and earlier, only HDD2
appears. Independent drive mode does not have this limitation when used
over USB or when used in OS X 10.8.4 and later.
2. When two hard drives are installed, only HDD2 will be available as a startup
drive in OS X. This happens in all versions of OS X and with both Thunderbolt
and USB. HDD1 can be used normally after the computer has started; HDD1
is only unavailable during the startup process. If only one drive is installed
in the Mercury Elite Pro Dual, it can be used in either the HDD1 or HDD2
position and it will be available as a startup drive.
Span Mode:
The drives show up as one large single volume. The total size will depend on the drives
installed; you can use drives of different capacities. A span is a configuration (not RAID) in
which the data is written sequentially across the drives. This combines the capacities of
the drives, but it does not provide any performance or redundancy benefits.
RAID 0 “Drive Striping” Mode:
The drives show up as one large single volume with a size equal to the combined
capacities of both drives. RAID 0 is used when speed is the primary objective, but
it does not have any redundancy for protection. Data is alternated very quickly
across both drives to gain speed by distributing the workload. This allows for
the fastest data transfer rates, but if one drive fails, the whole array can become
corrupted and data will be lost. Always maintain a backup of your data!
RAID 1 “Drive Mirroring” Mode:
The drives show up as one volume with a size equal to the capacity of one of the
two drives used in the array. RAID 1 copies (or “mirrors”) a set of data from the
rst drive to the second drive. This is useful when reliability and redundancy are
more important than capacity. When one drive fails, it can be replaced and the
data will be rebuilt automatically.
2.4 DRIVE FAILURE
In the event that one of the drives fails, the corresponding drive LED will blink red. If
the Mercury Elite Pro Dual was congured as a RAID 0 or Span, the data on the array
is lost and the volume cannot be used. For Span setups, data recovery software may
aid in retrieving les from the remaining functional drive. If the drives were congured
independently, then the data on the drive that did not fail will remain fully intact.

OWC Mercury Elite Pro Dual Specifications

General

Hot-swap	Yes
RAID levels	0, 1
Storage drive size	3.5 \
Total storage capacity	8000 GB
Number of storage drives supported	2
Interface	Thunderbolt
Product color	Aluminum
Storage temperature (T-T)	-40 - 65 °C
Operating temperature (T-T)	5 - 42 °C
Storage relative humidity (H-H)	5 - 95 %
Operating relative humidity (H-H)	8 - 90 %
Cache internal	128 MB

Weight and Dimensions

Depth	228.6 mm
Width	71.2 mm
Height	133.4 mm