Users Guide
If you have a redundant virtual disk, you can reconstruct the contents of a failed physical disk onto a new disk or a hot spare. A rebuild can
take place during normal operation, but it degrades performance.
A global hot spare drive can be part of dierent RAID level Virtual drives rebuilding operation on SWRAID controllers.
Managing Virtual Disk Bad Block Management
Virtual disk bad blocks are bad blocks on one or more member physical disks. The read operation on the virtual disks having bad blocks may
fail.
Storage Management generates a critical alert (2387) to notify you of the bad blocks on the virtual disk.
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 32. 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.
124 Virtual Disks