DELL 32XX User Manual

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The modeling process runs in the background until you run the stop command. The file parameter is 
optional. If used, it will write modeling results to the file you specify.
stop ssdCache [ssdCacheName]
performanceModeling file="filename"
Output is displayed directly on your screen, unless the file parameter is used. You can also access 
modeling results using MD Storage Manager.
NOTE: If you reboot a RAID controller module or make configuration changes to any SSD Cache 
options during the modeling run, no data will be saved.
Additional Information About SSD Cache And Performance Modeling
For complete description of the SSD Cache feature, see the Administrator's Guide.
The following additional SSD cache-related commands are available in this document:
• Change SSD Cache Application Type
• Blink SSD Cache
• Rename SSD Cache
• Resume SSD Cache
• Show SSD Cache
• Suspend SSD Cache
Troubleshooting and Diagnostics
If a storage array exhibits abnormal operation or failures, you can use the commands described in this 
section to determine the cause of the problems.
Collecting Physical Disk Data
To gather information about all the physical disks in a storage array, run the save allPhysicalDisks 
command. This command collects sense data from all the physical disks in a storage array and saves the 
data to a file. The sense data consists of statistical information maintained by each of the physical disks in 
the storage array.
Diagnosing A RAID Controller Module
The diagnose controller command’s testID parameter takes the following options, which you can 
use to verify that a RAID controller module is functioning correctly:
1
Reads the test
2
Performs a data loop-back test
3
Writes the test
The read test initiates a read command as it would be sent over an I/O data path. The read test 
compares data with a known, specific data pattern, checking for data integrity and errors. If the read 
command is unsuccessful or the data compared is not correct, the RAID controller module is considered 
to be in error and is placed offline.
Run the data loopback test only on RAID controller modules that have connections between the RAID 
controller module and the physical disks. The test passes data through each RAID controller module 
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