Users Guide

Virtual disk bad blocks are discovered when the controller performs any operation that requires scanning the disk. Examples of operations
that may result in this alert are:
Consistency check
Rebuild
Virtual disk format
I/O
Patrol Read
Recovering a physical disk bad block depends on the RAID level and state of the virtual disk. If a virtual disk is redundant, the controller can
recover a bad block on a physical disk. If a virtual disk is not redundant, then the physical disk bad block results in a virtual disk bad block.
Table 34. Sample Scenarios For Virtual Disk Bad Blocks
RAID Level Virtual Disk State Scenario Result
RAID 0 Degraded One bad block on a physical disk. The controller cannot regenerate
data from the peer disks as
there is no redundancy. This
results in a virtual disk bad block.
RAID 5 Ready One bad block on a physical disk. The controller regenerates data
from the peer disks and sends a
Write to the bad block. The disk
then remaps the Logical Block
Addressing (LBA) to another
physical location. The problem is
resolved.
RAID 5 Degraded One bad block on a physical disk. The controller cannot regenerate
data from the peer disks
because one drive is missing.
This results in a virtual disk bad
block.
RAID 5 Ready One bad block on two physical
disks at the same location.
The controller cannot regenerate
data from the peer disks. This
results in a virtual disk bad block.
RAID 6 Partially degraded (one failed/
missing physical disk)
One bad block on a physical disk. The controller regenerates data
from the peer disks and sends a
Write to the bad block. The disk
then remaps the LBA to another
physical location. The problem is
resolved.
RAID 6 Degraded (two failed/missing
physical disks)
One bad block on a physical disk. The controller cannot regenerate
data from the peer disks. This
results in a virtual disk bad block.
RAID 6 Ready One bad block on a physical disk. The controller regenerates data
from peer disks and sends a
Write to the bad block. The disk
then remaps the Logical Block
Addressing (LBA) to another
physical location. The problem is
resolved.
138 Virtual Disks