Attention: After you remove a E-DDM CRU, wait 70 seconds before replacing or reseating the E-DDM CRU to allow it to properly spin down. Failure to do so may cause undesired events.

8.Use the DS4000 Storage Manager subsystem management window to verify that the E-DDM is shown in the Storage Subsystem Management window.

Replacing multiple E-DDMs

This section provides guidelines for upgrading the E-DDMs in the storage subsystem. 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: After you remove a E-DDM CRU, wait 70 seconds before replacing or reseating the E-DDM CRU to allow it to properly spin down. Failure to do so may cause undesired events.

The following are methods for upgrading E-DDMs:

vReplacing all the E-DDMs at the same time

This method requires that you back up the data on the affected E-DDMs and then turn off the DS4700 Express storage subsystem.

Attention: Turn off the DS4700 Express storage subsystem before you turn off the attached storage expansion enclosures.

After replacing all the E-DDMs, you must reconfigure the new E-DDMs and restore data from backup. See the procedure in “Replacing all E-DDMs at the same time” on page 157.

This is the safest way to exchange E-DDMs 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 storage subsystem (or any storage expansion enclosures attached to the storage subsystem) until you finish the procedure. You must use this method on RAID 0 logical drives.

vReplacing the E-DDMs one at a time

In this method, you manually fail each E-DDM, replace it, and wait for the system to restore data to the new E-DDM before installing the next E-DDM. After you install the new E-DDMs, you can configure them to make the additional drive space available. See the procedure in “Replacing the E-DDMs one at a time” on page 159.

Using this method, you can replace the E-DDMs while the storage expansion enclosures and the DS4700 Express are running, eliminating the down time that is required if you replace all the E-DDMs 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 DS4700 manual Replacing multiple E-DDMs, Replacing all the E-DDMs at the same time, Replacing the E-DDMs one at a time