IBM DS4000 EXP810, Installation, User'S, And Maintenance Manual

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Enhanced Disk Drive Modules (E-DDMs)
Attention:
v You cannot mix storage expansion enclosures with different fibre channel speed
settings in the same drive channel/loop. All of the enclosures in a redundant drive
channel/loop pair must have the same enclosure speed setting. In addition, the
enclosure speed setting must be set at the
lowest operating enclosure speed.
v E-DDM options and FRUs for the EXP810 and DS4700 Express Storage
Subsystem are not the same as the Enhanced Value Disk Drive Modules
(EV-DDMs) and FRU options for the EXP420 and DS4200 Express Storage
Subsystem. Verify that the E-DDM option and FRU part numbers are correct
before inserting into the EXP810 and DS4700 Express drive slots. The disk drive
module CRUs for EXP420 storage expansion enclosures and DS4200 Express
Storage Subsystems appear as uncertified drives when inserted into EXP810
storage expansion enclosures and DS4700 Express Storage Subsystems and
vice versa.
The hot-swap drive bays that are accessible from the front of your storage
expansion enclosure are shown in Figure 1.
Figure 1. EXP810 hot-swap drive bays
The EXP810 supports up to 16 2 or 4 Gbps fibre channel (FC) or SATA E-DDMs.
The SATA E-DDMs have an ATA translator card that converts the fibre channel
protocol interface of the EXP810 drive channel/loop into the hard drive SATA
protocol interface. It also provides dual paths to the SATA drive for E-DDM CRU
path redundancy. Each SATA hard drive, ATA translator card (also referred to as a
interposer card), and carrier assembly (drive tray) are called SATA E-DDM CRUs.
The fibre channel E-DDMs consisted of the fibre channel and the carrier assembly
(drive tray).
Install E-DDM CRUs in the 16 drive bays on the front of the storage expansion
enclosure from the leftmost (slot 1) to rightmost (slot 16).
The EXP810 storage expansion enclosure drive channel operates at either 2 or 4
Gbps fibre channel interface speed. Ensure that the EXP810 enclosure speed
switch is set correctly for the 2 Gbps or 4 Gbps fibre channel E-DDM CRUs. The
EXP810 SATA E-DDM CRUs have an ATA translator card that converts E-DDM 3
Gbps SATA drive interface protocol to either 2 Gbps or 4 Gbps fibre channel
interface protocol. It is recommended to operate these SATA E-DDMs at 4 Gbps
fibre channel operating speed whenever the configuration allows, for example, when
no 2 Gbps fibre channel devices are in the configuration. The Link Rate setting
speed must be set accordingly. See “Verifying the Link Rate setting ” on page 101
for more information. The enclosure speed of the DS4000 Storage Subsystem that
the EXP810s are connected to must be set to the same fibre channel speed as the
EXP810 enclosure ID speed switch.
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IBM System Storage DS4000 EXP810 Storage Expansion Enclosure: Installation, User’s and Maintenance Guide