IBM Midrange System DS4000 Series Hardware Manual page 434

This can be started from the Logical view in the Storage Manager Storage Subsystem
window. First, highlight the array to be tested in the left-hand pane and select Advanced 
Recovery  Check Array Redundancy. Figure 7-61 shows the Check Redundancy window.
The array test starts after clicking the Start button.
Figure 7-61 Check redundancy window
The utility will return a status for each logical drive associated with the array:
Passed
Media error
Parity error
If parity errors are detected, then it is important to determine the root cause. Contact your
IBM Support representative for assistance.
A similar utility can also be run on an individual logical drive through the script editor in the
Storage Manager Enterprise Management window. The command syntax is:
check logicalDrive [logicalDriveName] parity [parityErrorFile=filename]
[mediaErrorFile=filename] [priority=(highest | high | medium | low | lowest)]
[startingLBA=LBAvalue] [endingLBA=LBAvalue] [verbose=(TRUE | FALSE)];
Here is a typical usage example:
check logicalDrive ["LUN01"] parity parityErrorFile="c:\LUN01.parity.txt"
mediaErrorFile="c:\LUN01.media.txt" priority=high verbose=TRUE;
This runs the RAID redundancy check on the entire logical drive named LUN01 with parity
errors being logged in the file c:\LUN01.parity.txt and any media errors in
c:\LUN01.media.txt.
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The logical drive passed the redundancy check. No inconsistencies
were detected in the redundancy information.
The disk drive media is defective and is unreadable.
The parity is not what it should be for a given portion of the data.