Working With Hot-Swap E-Ddms - IBM DS4000 EXP810 Installation, User's, And Maintenance Manual

Working with hot-swap E-DDMs

This section explains how you can increase the storage expansion enclosure
capacity by adding more E-DDMs or by replacing existing E-DDMs with ones that
have a larger capacity.
Before you begin, complete the following tasks:
v Read the safety and handling guidelines in "Safety" on page xi and in "Handling
v Ensure that your current system configuration is working properly.
v Back up all important data before you make changes to data storage devices.
Before you install or remove E-DDM CRUs, review the following information:
v Blank trays: A storage expansion enclosure without a full set of E-DDMs (16)
v E-DDM CRUs:
92
IBM System Storage DS4000 EXP810 Storage Expansion Enclosure: Installation, User's and Maintenance Guide
static-sensitive devices" on page 30.
contains blank trays in the unused drive bays. Before installing new E-DDMs, you
must remove these empty trays. Save the empty trays for future use. Each of the
16 bays must always contain either a blank tray or a hot-swap E-DDM.
For proper cooling and EMC protection, do not leave a drive slot open without
either a drive blank or a E-DDM CRU inserted.
– In this release, 2 or 4 Gbps fibre channel E-DDMs and SATA E-DDMs are
supported. The Link Rate setting speed must be set accordingly. See
"Verifying the Link Rate setting " on page 101 for more information.
– IBM recommends that when adding E-DDM CRUs, if you are not installing all
16 E-DDM CRUs into the EXP810, install the E-DDM CRUs from left to right
consecutively.
– For optimum performance, never insert a E-DDM into a storage expansion
enclosure without first confirming the drive firmware level. Contact IBM
Support for information on supported drive firmware levels.
– Use of non-supported drives in the storage expansion enclosures can cause
the storage expansion enclosures to fail.
– In configurations with mixed storage expansion enclosures, all storage
expansion enclosures on a fibre loop must be operating at the same interface
speed.
– Ensure that the speed of the drive CRU you are adding is supported in the
storage expansion enclosure. For example, do not install a 2 Gbps drive CRU
in a storage expansion enclosure that supports only 4 Gbps drives.
– Drive CRUs are not interchangeable between EXP100s, EXP710s, EXP420s,
and EXP810s.
– After you remove an E-DDM CRU, wait 70 seconds before replacing or
reseating it to allow it to properly spin down. Failure to do so may cause
undesired events.