Disk initialization
For physical disks, initialization writes metadata to the physical disk so that the controller can use the physical disk.
Background Array Scan
Verifies and rectifies correctable media errors on mirror, volume, or parity data for virtual disks. Background Array Scan (BAS) starts
automatically after a virtual disk is created while in the operating system.
Checkpointing
Allows different types of checkpointing to resume at the last point following a restart. After the system restarts, background checkpointing
resumes at its most recent checkpoint.
Three types of checkpointing are available:
•
Consistency check (CC)
•
Background initialization (BGI)
•
Rebuild
Consistency check
Consistency check (CC) is a background operation that verifies and corrects the mirror or parity data for fault-tolerant physical disks. It is
recommended that you periodically run a consistency check on the physical disks.
By default, CC corrects mirror or parity inconsistencies. After the data is corrected, the data on the primary physical disk in a mirror set is
assumed to be the correct data and is written to the secondary physical disk mirror set.
The CC operation reports data inconsistencies through an event notification. A CC cannot be user-initiated in the BIOS Configuration Utility
(Ctrl+R). However, CC can be initiated using OpenManage Server Administrator Storage Management. For more information, see OMSA
user’s guide at
dell.com/openmanagemanuals
.
Background initialization
Background initialization (BGI) of a redundant virtual disk creates the parity data that allows the virtual disk to maintain its redundant data
and survive a physical disk failure. Similar to consistency check (CC), BGI helps the controller to identify and correct problems that might
occur with the redundant data at a later time.
CAUTION:
Data is lost if a physical disk fails before the completion of a BGI operation.
BGI allows a redundant virtual disk to be used immediately.
NOTE:
Although a BGI is software-initiated from within the BIOS Configuration Utility (accessible through Ctrl + R), the PERC
S140 drivers must be loaded before the BGI runs.
Automatic virtual disk rebuild
Rebuilds a redundant virtual disk automatically when a failure is detected if a hot spare is assigned for this capability.
Virtual Disks
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