IBM N Series, Hardware Manual

Page: 71 / 368

Chapter 5. Expansion units
51
5.4 Expansion unit EXN3500
The EXN3500 is a small form factor (SFF) 2U disk storage expansion unit for mounting in any
industry standard 19-inch rack. The EXN3500 provides low-cost, high-capacity SAS disk
storage with slots for 24 hard disk drives for the IBM N series system storage family.
The EXN3500 SAS expansion unit is shipped with no disk drives unless they are included in
the order. In that case, the disk drives are installed in the plant.
The EXN3500 SAS expansion unit is a 2U SFF disk storage expansion unit that must be
mounted in an industry-standard 19-inch rack. It can be attached to all N series systems
except N3300, N3700, N5200, and N5500. It includes the following features:
򐂰 Third-generation SAS product
򐂰
Increased density
򐂰 24 x 2.5 inch 10 K RPM drives in 2U rack at same capacity points (450 GB and 600 GB)
offers double the GB/rack U of the EXN3000
򐂰
Increased IOPs/rack U
򐂰 Greater bandwidth
򐂰
6 Gb SAS 2.0 offers ~24 Gb (6 Gb x 4) combined bandwidth per wide port
򐂰 Improved power consumption: Power consumption per GB reduced by approximately
30-50%*
򐂰
Only SAS drives are supported in the EXN3500: SATA is not supported
The following features were not changed:
򐂰 Same underlying architecture and FW base as EXN3000
򐂰
All existing EXN3000 features and functionality
򐂰 Still uses the 3 Gb PCIe Quad-Port SAS HBA (already 6 Gb capable) or onboard SAS
ports
Total thermal
dissipation, BTU/hr 3 TB 2970 1122 2243 3137 1181 2362
4 TB 2909 1155 2309 2854 1120 2240
Weight With midplane, four PSUs, two IOMs, four HDD carriers: 81 lbs (36.7 kg)
Fully configured: 145 lbs (65.8 kg)
a. Worst-case indicates a system that is running with two PSUs, high fan speed, and power that is distributed over
two power cords.
b. Per PSU pair indicates typical power needs, per PSU pair, for a system operating under normal conditions.
c. System indicates typical power needs for four PSUs in a system operating under normal conditions and power that
is distributed over four power cords.
Input voltage 100 to 240 V (100 V actual 200 to 240 V (200 V actual)
Size Worst
case,
2 PSU
a
Typical Worst
case,
2 PSU Typical
Per PSU
pair
b
System,
four PSU
c
Per PSU
pair System,
four PSU