IBM TotalStorage EXP100, Installation, User'S, And Maintenance Manual

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Replacing multiple drives
This section provides guidelines for upgrading the drives in the expansion
enclosure. Read the software documentation and this entire section to determine if
you should use this procedure, use a modified version of this procedure, or use a
different procedure that is provided by your operating system.
Note: Instructions that are provided with your software should supersede anything
stated in this document.
Attention:
v 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.
v Before you insert the new SATA drive option or drive CRU/FRU into the DS4000
configuration, you must ensure that the installed DS4000 controller and EXP100
ESM have the minimum controller and ESM firmware versions that are required
for the new SATA drive. Always check the documentation that is included with the
new drive to find out the minimum controller and ESM firmware versions, or any
prerequisite tasks, for DS4000 controller and EXP100 ESM.
There are two methods for upgrading drives:
v Replacing all the drives at the same time
This method requires that you back up the data on the affected drives and then
turn off the EXP100 and the DS4000.
Attention: Turn off the DS4000 before you turn off the EXP100.
After replacing all the drives, you must reconfigure the new drives and restore
data from backup. See the procedure in “Replacing all drives at the same time”
on page 79.
This is the safest way to exchange drives without losing data. However, this
method might take a long time to complete because of the backup,
reconfiguration, and restoration processes. In addition, other users are not able
to use the DS4000 storage subsystem (or any expansion enclosures attached to
the storage subsystem) until you finish the procedure. You must use this method
on RAID 0 logical drives.
v Replacing the drives one at a time
In this method, you manually fail each drive, replace it, and wait for the system to
restore data to the new drive before installing the next drive. After you install the
new drives, you can configure them to make the additional drive space available.
See the procedure in “Replacing the drives one at a time” on page 81.
Using this method, you can replace the drives while the EXP100 and the DS4000
are running, eliminating the down time that is required if you replace all the
drives at once. However, this method is more risky because you can lose data if
the drive restoration or storage subsystem reconfiguration process fails. In
addition, the reconstruction process might take a long time. This method works
only on redundant logical drives (RAID 1, 3, or 5). You cannot use this method
with any drives containing RAID 0 logical drives.
Consider backing up your data if you use this method. This safeguards your data
if the restoration and reconfiguration process fails or the new drive malfunctions.
The method you use depends on the following considerations:
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IBM TotalStorage DS4000 EXP100 Storage Expansion Enclosure: Installation, User’s and Maintenance Guide