Enclosure Id Settings; Sas Cabling - IBM DS3000 Introduction And Implementation Manual

7065Cabling.fm

3.1 Enclosure ID settings

The DS3000 storage subsystem can be attached to up to three EXP3000 enclosures. For
proper operation, you have to set a unique 'enclosure ID for the DS3000 and for each of the
EXP3000s. This is very important, because the enclosure ID, along with the drive's position
within the enclosure, is used to determine the hardware address of each hard disk drive. If
two enclosures are configured with the same enclosure ID, the disk drives will have
conflicting hardware addresses.
If the DS3000 is used standalone and is not connected to any EXP3000s, then the enclosure
ID setting does not really matter. But if any EXP3000s will ever be attached, make sure you
verify the ID settings on each enclosure.
The factory default enclosure ID of the DS3000 controller is 85. We recommend that you
leave this as it is. If you do decide to change it, we recommend using values 80 or higher,
since some storage subsystems may not support values lower than 80.
In a dual controller DS3000 subsystem, both controllers should have the same enclosure ID.
Similarly, on an EXP3000 with two ESMs, both ESMs must have the same enclosure ID.
You can view and change the enclosure IDs with the DS3000 Storage Manager or using the
CLI. Valid enclosure ID values are 0 to 99.
See 11.2.6, "Change Enclosure ID Numbers" on page 260 for information on how to change
the enclosure ID. On the CLI, use the command
set enclosure [ serial-number ] id = enclosure-id.

3.2 SAS cabling

All DS3000 storage subsystems, regardless of the type of host attachment, use SAS disk
drives and SAS cabling to attach expansion enclosures. Therefore, let's have a look at the
SAS cables and connectors used.
The SAS ports on the DS3000 controller and EXP3000 ESM all support mini-SAS 4x
multilane connectors. SAS cables with mini-SAS connectors that will fit in these ports are
required, as shown in Figure 3-1. IBM provides SAS cables in two cable lengths: one and
three meters.
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IBM System Storage DS3000: Introduction and Implementation Guide
Draft Document for Review August 30, 2007 12:59 am