Specifications

Recovering from Hard Drive Failure
82 MSA1000 Reference Guide
There are several other ways to recognize that a hard drive has failed:
■ The amber status indicator will light up on the front of an HP storage system
if failed drives are inside. (Other problems such as fan failure, redundant
power supply or over-temperature conditions will also cause this indicator to
light up.)
■ A front panel display message will list failed drives whenever the system is
restarted, as long as the controller detects one or more good drives.
■ Insight Manager can detect failed drives locally or remotely across a network.
Additional information on troubleshooting hard drive problems can be found in
the Server Troubleshooting Guide.
Compromised Fault Tolerance
Compromised fault tolerance commonly occurs when more physical drives have
failed than the fault tolerance method can endure. In this case, the logical volume
will be failed and error messages will be returned to the host. Data loss is likely to
occur.
An example of this situation would be a RAID 5 logical drive, where one drive on
an array fails while another drive in the same array is still being rebuilt.
Fault tolerance may also be compromised due to non-drive problems, such as a
faulty cable, faulty storage system power supply, or a user accidentally turning off
an external storage system while the host system power was on. In such cases, the
physical drives do not need to be replaced. However, data loss may still have
occurred, especially if the system was busy at the time the problem happened.