IBM TotalStorage EXP100, Инструкция по установке, использованию и обслуживанию

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management software uses the enclosure ID to provide a correlation between the
storage management graphics and the physical expansion enclosure. The ID
indicates which physical unit corresponds to the storage management software
status.
Use the end of a paper clip to push the buttons on the enclosure ID switches X10
and X1 to set the enclosure ID of the EXP100 to any value from 0 - 77. See
Figure 27. Each expansion enclosure that is connected to a DS4000 should have a
unique ID. The ID must be different from all other expansion enclosures that are
connected to the DS4000 storage subsystem.
In addition, DS4000 controllers use a combination of the enclosure ID and the
number of the physical slot that a Fibre Channel hard drive occupies to create a
unique Fibre Channel loop address or arbitrated loop physical address (AL_PA) for
each drive in a Fibre Channel drive loop.
Give each storage expansion enclosure in a redundant drive loop a unique ones
(x1) digit ID. This setting will enforce hard AL_PAs (unchangeable between Fibre
Channel Loop Initializations [LIPs]) for the drives and facilitate drive loop problem
troubleshooting in the event of an error. If the ID is not unique, two or more devices
will have the same hard AL_PA. In such a case, the controller will use soft AL_PAs
for the devices that have identical hard AL_PAs. Use the enclosure ID tens (x10)
digit setting for the storage expansion enclosures in the second redundant drive
loop.
The problem with soft addressing is that addresses may change between LIPs. This
possibility increases the difficulty of troubleshooting drive loop problems because it
is not easy to ascertain whether the same device with a different address or a
different device may be causing a problem.
Expansion enclosure speed settings
The default switch setting is 2 Gbps. This is the only speed setting allowed for the
EXP100.
Attention: Do not remove the metal plate that covers the expansion enclosure
speed setting. Do not adjust the expansion enclosure speed setting.
Figure 27. Enclosure ID settings
Chapter 2. Installing the EXP100
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