Compromised Fault Tolerance - Compaq Smart Array 221 User Manual

E-6 Recovering from Drive Failure
During Automatic Data Recovery, if the online LED of the replacement drive
stops blinking and the replacement drive is failed (amber failure LED
illuminated or other LEDs go out), the replacement drive is producing
unrecoverable disk errors. In this case, the replacement drive should be removed
and replaced with another replacement drive.

Compromised Fault Tolerance

If fault-tolerance is ever compromised due to failure of multiple drives, the
condition of the logical drive will be "failed" and "unrecoverable" errors will be
returned to the host. Data loss is probable. Insertion of replacement drives at this
time will not improve the condition of the logical drive. If this occurs, first try
turning the entire system off and on. In some cases an intermittent drive will
appear to work again (perhaps long enough to make copies of important files)
after cycling power. If a 1779 POST message displays, press F2 to reenable the
logical drive(s). Remember that data loss has likely occurred and any data on
the logical drive is suspect.
Fault-tolerance may 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,
obviously the physical drives do not need to be replaced. However, data loss can
still occur in this situation, especially if the system was busy at the time the
problem developed.
In cases of "legitimate" drive failure, once copies of important data have been
made (if possible), replace any drives that have failed to prevent further drive
problems in the future. After these (multiple) drives are replaced, the fault-
tolerance may again be compromised, power may need to be cycled, and the
1779 POST message may again be displayed. Press F2 to reenable the logical
drive(s), recreate your partitions, and restore all data from backup.
Because of the risk that fault tolerance may be compromised at some point in
the future, make regular backups of all logical drives.
Writer: Karen Hale Project: Compaq Smart Array 221 Controller User Guide Comments: 388541-001
File Name: M-APPE.DOC Last Saved On: 11/5/98 12:29 PM
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