- IBM switch Users and Maintenance Guide

Attention: After you remove a drive CRU, wait at least 70 seconds before
replacing or reseating the drive CRU to allow the drive to properly spin down.
Failure to do so may cause undesired events.
Before you install or remove drive CRUs, review the following information:
v Blank trays: A storage server without a full set of drives (14) contains blank
trays in the unused drive bays. Before installing new drives, you must remove
these empty trays. Save the empty trays for future use. Each of the 14 bays
must always contain either a blank tray or a hot-swap hard disk drive.
Note:
For proper cooling and EMC protection, do not leave a drive slot open
without either a blank tray or a hard disk drive CRU inserted.
v Drive CRUs: The DS4100 supports up to fourteen IBM 1.5 Gbps SATA hard disk
drives.
Note: Do not use fibre-channel hard disk drive CRUs in the DS4100.
These drives come preinstalled in drive trays. This drive-and-tray assembly is
called a drive CRU. You can install the drive CRUs in the 14 drive bays on the
front of the storage server.
v Drive CRU labels: A label is provided on the front of each hard disk drive. Use
this label to record the location information for each drive before you remove it.
Ensure that you keep track of the drives and their corresponding bays. Also,
record the location information in Table 19 on page 119. If you install a drive in
the wrong bay, you might lose data.
v Drive LEDs: Each drive tray has two associated LEDs, a green Activity LED and
an amber Fault LED, on the chassis of the DS4100. These LEDs indicate the
status for that drive. See Table 16 for the drive LED states and descriptions.
Table 16. Drive LED activity
LED LED state Descriptions
Activity LED Flashing green The green LED flashes to indicate fibre-channel activity to
the drive.
Activity LED Steady green The green LED lights to indicate that the drive is properly
installed and is spun up by the DS4000 controller.
Fault LED Flashing
amber
The amber LED flashes to indicate that a drive has been
identified by the software.
Fault LED Steady amber The amber LED lights to indicate a drive failure.
Activity and
Fault LEDs
All unlit The storage server is powered off.
v Fibre-channel loop IDs: When you install a drive CRU in the storage server, the
drive CRU connects into a printed circuit board called the midplane. The
midplane automatically sets the fibre-channel loop ID to the default value 00.
v Hot-swap hardware: The storage server contains hardware that you can use to
replace a failed hard disk drive without turning off the storage server. Therefore,
you can continue operating the system while a hard disk drive is removed or
installed. These drives are known as hot-swap drives.
Installing hot-swap hard disk drives
You can install hard disk drives while the storage server is turned on and running.
Complete the following steps to install hot-swap hard disk drives in the storage
server:
80 IBM TotalStorage DS4100 Storage Server: Installation, User’s, and Maintenance Guide