Source
RETAIN tip: H193840
Symptom
In previous levels of microcode for the TotalStorage DS4000, the battery expiration notification was triggered at 36 months, followed by a cache disable action by the microcode at 39 months.
This microcode was purely a date-driven method for battery expiration notification (as opposed to a diagnostic).
After the cache was disabled by the microcode at 39 months, users experience degraded performance.
Affected configurations
The system may be any of the following IBM servers:
- DS4200 Storage Server, type 1814, any model
- DS4300 (FAStT600) Dual Controller and Turbo Storage Server, type 1722, any model
- DS4300 (FAStT600) Single Controller Storage Server, type 1722, any model
- DS4500 (FAStT900) Storage Server, type 1742, any model
- DS4700 Storage Server, type 1814, any model
- DS4700 Storage Server, type 1814 (DC power supplies), any model
- DS4800 Storage Server, type 1815, any model
This tip is not software specific.
This tip is not option specific.
Solution
This behavior is fixed in the firmware level 6.60.02.00.
The file is available from the IBM Storage Support web site at the following URL:
http://www.ibm.com/systems/support/
Additional information
After an extensive review process, IBM found that the batteries, in general, operated well past 62 months.
In order to minimize premature replacements of a battery and to lengthen the time before the user would experience performance degradation due to a cache disable action related to the battery’s expiration, IBM changed the microcode so that the battery expiration notification would be triggered a little after 62 months followed by the cache disable action by the microcode a little after 10 years.
Note: If a battery actually does fail before the battery expiration notification is triggered, then the diagnostic package on the DS4000 will identify that battery failure and Power On Self Test (POST) an error message.
The following is an example of what users may see after installing the new code:
Battery Status Optimal:
Age: 541 day (s)
Days until Replacement: 3,148 day(s)
Once the new battery expiration notice is triggered, users should determine how much affected they would be to having the cache disabled. An appropriate response to the expiration then should be taken.
If there would be little to no impact if the cache were disabled, then there may not be an immediate need to have the battery replaced.
If the impact would be more significant, then a user should consider replacing the battery more quickly to ensure that the 10-year timer is not triggered.
Note: There have been some reports of cache being disabled at 62 months at the battery expiration notification on 6.60.xx.xx and newer controller firmware.
There is no fix for this if it occurs.
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