Drive Maintenance
Scenario 2
:
Only one hard disk drive fails.
A hot-spare drive is not defined or is smaller than the failed
drive.
The logical drives in the array are assigned RAID levels 0, 1, 5,
or a combination of these levels.
All data in logical drives assigned RAID level 0 will be lost. In this
array, the logical drives that are assigned RAID level 1 or 5 will be
in Critical (CRT) state. The logical drives assigned RAID level 0
will be in the Offline (OFL) state.
Scenario 3
:
If more than one drive in an array fails, all the data is lost in all of
the logical drives of the array. For this reason, it is important that
you replace and rebuild a defunct drive as soon as possible.
Logical and Hard Disk Drive Status Indications
The status of the hard disk drive determines the status of the logical
drives in the array in which the hard disk is grouped.
A single hard disk drive failure, (indicated by a DDD status in
the Bay/Array selection list), generates a CRT status for the
array's logical drives that are assigned levels 1 and 5. Data in
logical drives with a CRT is not lost. You must replace the one
defunct hard disk drive promptly, and perform a Rebuild
operation. If two hard disk drives were to fail, all of the data in
the array would be lost.
After you install a new hard disk drive, the Replace process
changes the drive status from DDD to RBL if the array contains
a CRT logical drive. After the Rebuild process, the hard disk
drive status changes from RBL to ONL.
A multiple hard disk drive failure causes logical drives in that
array that to have an Offline (OFL) status. This means that data
is lost in all the logical drives in that array, regardless of which
RAID level is assigned.
Chapter 3. Configuring the Disk Array
105
Summary of Contents for PC Server 520
Page 1: ...PC Server 520 User s Handbook for PCI Micro Channel IBM...
Page 86: ...Installation Checklist 70 PC Server 520 User s Handbook for PCI Micro Channel...
Page 146: ...Using the Mini Configuration Program 130 PC Server 520 User s Handbook for PCI Micro Channel...
Page 190: ...Using the SCSISelect Utility Program 174 PC Server 520 User s Handbook for PCI Micro Channel...
Page 385: ...Installing Additional Test Programs 207 CMD 3 Chapter 7 Solving Problems 369...
Page 438: ...IBM Part Number 78H6336 Printed in U S A May 1996 78H6336...