Promise Technology Pegasus3 R4 User Manual

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Promise Technology Pegasus3 R4/R6/R8
Capacity Coercion
This feature is designed for fault-tolerant logical drives (RAID 1, 1E, 5, 6, and 10). It is generally
recommended to use physical drives of the same size in your disk arrays. When this is not possible,
the system adjusts for the size differences by reducing or coercing the capacity of the larger drives to
match the smaller ones. With Pegasus, you can choose to enable capacity coercion and any one of
four methods.
Enable capacity coercion and choose the method in the Controller Settings menu. See “Making
Controller Settings” on page 25.
The choices are:
• GBTruncate– (Default) Reduces the useful capacity to the nearest 1,000,000,000 byte
boundary.
• 10GBTruncate– Reduces the useful capacity to the nearest 10,000,000,000 byte
boundary.
• GroupRounding– Uses an algorithm to determine how much to truncate.
Results in the maximum amount of usable drive capacity.
• TableRounding–Appliesapredenedtabletodeterminehowmuchtotruncate.
Capacity coercion also affects a replacement drive used in a disk array. Normally, when a physical
drive fails, the replacement drive must be the same capacity or larger. However, the capacity coercion
feature permits the installation of a replacement drive that is slightly smaller (within 1 gigabyte) than
the remaining working drive. For example, the remaining working drives can be 80.5 GB and the
replacement drive can be 80.3, since all are rounded down to 80 GB. This permits the smaller drive to
be used.
Without capacity coercion, the controller does not permit the use of a replacement physical drive that is
slightly smaller than the remaining working drives.

Promise Technology Pegasus3 R4 Specifications

General

Internal	No
Chassis type	Tower
Cooling type	Active
Device class	Small & Medium Business
Fan diameter	92 mm
Certification	CB, UL, cUL, TUV , BSMI, SPRING, BIS FCC, CE-EMC, VCCI, BSMI, RCM KCC
Product color	Black
LED indicators	Yes
Number of fans	1 fan(s)
Airflow (imperial)	70 cfm
Management platform	Pegasus Utility
Cable lock slot type	Kensington
RAID levels	0, 1, 1E, 5, 6, 10
Data transfer rate	40 Gbit/s
Storage drive size	3.5 \
Storage drive capacity	4000 GB
Storage drive interface	Serial ATA
Installed storage drive type	HDD
Supported storage drive types	HDD & SSD
Total installed storage capacity	16 TB
Maximum supported storage capacity	- TB
Number of storage drives installed	4
AC input voltage	100-230 V
AC input frequency	50 - 60 Hz
Number of power supply units	1
Power supply unit (PSU) capacity	250 W
Thunderbolt version	3
Thunderbolt ports quantity	2
Storage temperature (T-T)	-40 - 70 °C
Operating temperature (T-T)	5 - 35 °C
Storage relative humidity (H-H)	5 - 95 %
Operating relative humidity (H-H)	10 - 95 %
Cables included	AC, Thunderbolt

Weight and Dimensions

Depth	188 mm
Width	248 mm
Height	195 mm
Weight	6800 g