Hard Drive Installation and Replacement

CAUTION: Sometimes, a drive that has previously been failed by the controller may seem to be operational after the system is power-cycled, or (for a hot-pluggable drive) after the drive has been removed and reinserted. However, continued use of such marginal drives may eventually result in data loss. Replace the marginal drive as soon as possible.

There are several other factors to remember when replacing a hard drive:

•Non-hot-pluggable drives should be replaced only while the system is powered down.

•Hot-pluggable drives can be removed and replaced at any time, whether the host or storage system power is on or off.

When a hot-pluggable drive is inserted, all disk activity on the array pauses while the new drive is spinning up (usually 20 seconds or so). If the drive is inserted while power is on, in a fault-tolerant configuration, data recovery to the replacement drive begins automatically (indicated by the blinking Online LED).

•Replacement drives must have a capacity no less than that of the smallest drive in the array. The controller immediately fails drives that have insufficient capacity, before automatic data recovery can begin.

•When you set the SCSI ID jumpers manually, check the ID value to be sure that the correct physical drive is being replaced. Set the same ID value on the replacement drive to prevent SCSI ID conflicts.

CAUTION: In systems using external data storage, take care that the server is the first unit to be powered down and the last to be powered back up. Doing this ensures that the system does not erroneously mark the drives as failed when the server is next powered up.

The rebuild operation takes several hours, even if the system is not busy while the rebuild is in progress. System performance and fault tolerance are both affected until the rebuild has finished. Therefore, replace drives during low activity periods whenever possible. In addition, be sure that all logical volumes on the same array as the drive being replaced have a current, valid backup.

HP Smart Array 641/642 Controller User Guide

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