
Drive procedures 22
For example, fault tolerance might occur when a drive in an array fails while another drive in the array is
being rebuilt.
Compromised fault tolerance can also be caused by problems unrelated to drives. In such cases,
replacing the physical drives is not required.
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.
Power down the entire system, and then power it back up. In some cases, a marginal drive will work
again for long enough to enable you to make copies of important files. If a 1779 POST message is
displayed, do the following:
a.
Press the
F2
key and select Device Health Status.
b.
Select 1779 from the list of errors.
c.
Use the actions on the submenu to re-enable the logical volumes.
Remember that data loss has probably occurred and any data on the logical volume is suspect.
2.
Make copies of important data, if possible.
3.
Replace any failed drives.
4.
After you have replaced the failed drives, fault tolerance may again be compromised. If so, cycle the
power again. If the 1779 POST message is displayed:
a.
Press the
F2
key and select 1779 from the list of errors. Then, use the actions on the submenu to
re-enable the logical drives.
b.
Recreate the partitions.
c.
Restore all data from backup.
To minimize the risk of data loss that is caused by compromised fault tolerance, make frequent backups of
all logical volumes.
Replacing drives
The most common reason for replacing a drive is that it has failed. However, another reason is to
gradually increase the storage capacity of the entire system.
For systems that support hot-pluggable drives, if you replace a failed drive that belongs to a fault-tolerant
configuration while the system power is on, all drive activity in the array pauses for 1 or 2 seconds while
the new drive is initializing. When the drive is ready, data recovery to the replacement drive begins
automatically.
If you replace a drive belonging to a fault-tolerant configuration while the system power is off, a POST
message appears when the system is next powered up. This message prompts you to press the
F1
key to
start automatic data recovery. If you do not enable automatic data recovery, the logical volume remains in
a ready-to-recover condition and the same POST message appears whenever the system is restarted.
Before replacing drives
•
Open Systems Insight Manager, and inspect the Error Counter window for each physical drive in the
same array to confirm that no other drives have any errors. For more information about Systems
Insight Manager, see the documentation on the Insight Management DVD or on the Hewlett Packard
Enterprise website (
http://www.hpe.com/info/insightmgmt
•
Be sure that the array has a current, valid backup.