Users Guide
• 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 26. 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.
Recommendations For Clearing Bad Blocks
Storage Management allows you to clear the bad block warnings. To clear bad blocks, the following procedure is recommended:
1 Perform a backup of the virtual disk with the Verify option selected.
One of the following scenarios may occur:
• Backup operation fails on one or more les. In this case, restore the le from a previous backup. After restoring the le, proceed to
step 2.
Virtual Disks
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