vBlank trays: A storage subsystem without a full set of E-DDMs (16) 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 an E-DDM CRU inserted.
vE-DDM CRUs:
– The DS5020 storage subsystem supports 4 Gbps Fibre Channel and SATA
E-DDMs. The link rate setting speed must be set accordingly.See “Verifying
the link rate setting” on page 136 for more information.
– When adding E-DDM CRUs, if you are not installing all 16 E-DDM CRUs into
the storage subsystem, install the E-DDM CRUs from left to right
consecutively.
– For optimum performance, never insert an E-DDM into a storage subsystem
without first confirming the drive firmware level. In the event of a drive
firmware mismatch, schedule down time as soon as possible to upgrade the
drive firmware to the same version. For information about supported drive
firmware versions, refer to the IBM Storage Systems support Web site:
http://www.ibm.com/systems/support/storage/disk
– Use of non-supported drives in the drive modules can cause the storage
subsystem 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.
– Make sure that the speed of the E-DDM CRU you are adding is supported in
the storage subsystem. For example, do not install a 2 Gbps E-DDM CRUs in
a storage subsystem that supports only 4 Gbps E-DDMs.
– E-DDM CRUs are not interchangeable between EXP520 and EXP810 storage
expansion enclosures.
– 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 might cause
undesired events.
Attention:
Before you turn on the power to the DS5020 storage subsystem, it must be
populated with at least two E-DDMs.
If at least two E-DDMs are not installed in the DS5020, an insufficient load to the
enclosure power supplies might cause them to intermittently appear as failed,
falsely indicating the power supplies are bad. All of the E-DDMs in the DS5020
storage subsystem and the connected storage expansion enclosure or
enclosures must contain no prior configuration data.
vE-DDM CRU labels: Alabel is provided on the front of each E-DDM. Use this
label to record the location information for each E-DDM before you remove it.
Make sure that you keep track of the E-DDMs and their corresponding bays.
Also, record the location information in Table24 on page 166. If you install an
E-DDM in the wrong bay, you might lose data.
vE-DDM LEDs: Each E-DDM CRU tray has two associated LEDs, a green Activity
LED and an amber Fault LED. These LEDs indicate the status for that drive. See
Table18 on page 128 for the E-DDM LED states and descriptions.
Chapter5. Replacing components 127