Cache Backup Device Diagnostics
After you replace a cache backup device, run the cache backup device diagnostics to check the status of the cache backup device.
The Cache Backup Device diagnostics option is not available unless these conditions are met:
- The controller must be in Service mode.
- The storage array must have a field-replaceable data cache backup device connected to it on either controller.
- The controller firmware must support cache backup device diagnostics.
In the Cache Backup Device Diagnostic dialog, the status of each device is shown. The device can be one of these statuses:
- Optimal
- Failed
- Removed
- Unknown
- Write Protected
- Incompatible
Select the device, and then you can choose to run either basic diagnostics or extended diagnostics.
Basic Diagnostics
The Basic option validates the ability of the cache memory to transport I/O data.
Basic diagnostics should take less than one minute to complete. A progress bar displays during the process to show the status
of the basic diagnostics. To cancel the basic diagnostics process, click Cancel.
Extended Diagnostics
The Extended option performs an in-depth examination of the ability of the cache backup device to function.
Two options are available for extended diagnostics:
-
Random patterns test – This test writes a random pattern to each flash block within the USB flash device. The randomly generated pattern is written
to any randomly selected page within the flash block to be written. The pattern written is read back and verified. The randomly
selected pattern is written to the raw pool within the cache memory. The data is copied to the processor memory first and
is then sent through the direct memory access to the USB flash drives.
-
Write patterns test – This test writes a pattern to the entire USB flash drive in blocks. Each block written is read back, and the data is verified
for integrity purposes.
The extended diagnostics might take several minutes to complete. A progress bar displays during the process to show the status
of the extended diagnostics. To cancel the extended diagnostics process, click Cancel.
Results
For each test, the diagnostics return these results:
-
The diagnostics complete successfully – The Results table shows each test name and the associated result.
-
The diagnostics do not complete because of an error – The Results table shows the test name and the associated error information.
-
The diagnostics do not complete because the user canceled the diagnostics – The Results table is populated with the string, Diagnostics canceled by user. After a line break, the completed tasks and their results are presented to the user on separate lines.