DELL 32XX User Manual

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Recovered 
media error
The physical disk could not read the requested data on its first attempt. 
The result of this action is that the data is rewritten to the physical disk and 
verified. The error is reported to the MEL.
Consistency 
mismatches
Consistency errors are found, and a media error is forced on the block stripe so 
that it is found when the physical disk is scanned again. If consistency is 
repaired, this forced media error is removed. The result of this action is that the 
first ten consistency mismatches found on a virtual disk are reported to the 
MEL.
Unfixable error
The data could not be read and consistency information could not be used to 
regenerate it. For example, consistency information cannot be used to 
reconstruct data on a degraded virtual disk. The result of this action is that the 
error is reported to the MEL.
The script command set provides four commands to define media scan properties:
• set virtualDisks
• set storageArray
• set snapGroup
• set snapVirtualDisk
The set virtualDisk command enables a media scan for the virtual disk. The following syntax is the 
general form of the command:
set (allVirtualDisks | virtualDisk
[virtualDiskName] | virtualDisks [virtualDiskName1
... virtualDiskNamen] | virtualDisk <wwid>
mediaScanEnabled=(TRUE | FALSE)
The set storageArray command defines how frequently a media scan is run on a storage array. The 
following syntax is the general form of the command:
set storageArray mediaScanRate=(disabled | 1-30)
The set snapVirtualDisk and set snapGroup commands run media scans on physical disks that 
are members of snapshots and snapshot groups. The following examples show command syntax:
set snapVirtualDisk ["snapvirtualDiskName"]
mediaScanEnabled=(TRUE | FALSE)
set snapGroup ["snapGroupName"]
mediaScanEnabled=(TRUE | FALSE)
Running A Consistency Check With A Media Scan
Consistency checks are performed when media scans are run, if consistency check is enabled on the 
virtual disk. During a consistency check, all data blocks in a virtual disk are scanned, and deteriorated data 
is corrected. The method of correction depends on the redundant array of independent disks (RAID) 
levels:
RAID 5 and 
RAID 6 virtual 
disks
Consistency is checked and repaired.
RAID 1 virtual 
disks
The data is compared between the replicated physical disks, and data 
inconsistencies are repaired.
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