HP StorageWorks 500 G2 Modular Smart Array - Manual (Page 80)

80 HP StorageWorks MSA500 G2 Storage System User Guide
One example of a situation in which compromised fault tolerance may occur is
when a drive in an array fails while another drive in the array is being rebuilt. If
the array has no online spare, any logical drives in this array that are configured
with RAID 5 fault tolerance will fail.
Compromised fault tolerance can also be caused by non-drive problems, such as
a faulty cable or temporary power loss to a storage system. In such cases, you do
not need to replace the physical drives. However, you may still have lost data,
especially if the system was busy at the time that the problem occurred.
Recovering from compromised fault tolerance
If fault tolerance is compromised, inserting replacement drives does not improve
the condition of the logical volume. Instead, if the screen displays unrecoverable
error messages, perform the following procedure to recover data:
1. Check for loose, dirty, broken, or bent cabling and connectors on all devices.
2. Power down the storage system (on page 28 ).
3. Power up the storage system (on page 27 ).
In some cases, a marginal drive will work again for long enough to enable
you to make copies of important files.
4. If an 02 or 04 controller display message is displayed, press the Right button
to re-enable the logical volumes. Remember that data loss has probably
occurred and any data on the logical volume is suspect.
5. Make copies of important data, if possible.
6. Replace any failed drives.
7. After you have replaced the failed drives, fault tolerance may again be
compromised. If so, cycle the power again, and if the 02 or 04 controller
display message is displayed, press the Right button to re-enable the logical
volumes.