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TL;DR - Is the immediate failure of a replacement battery, for a failed battery, on a battery backed accelerator for a Smart Array P400 controller a common occurrence? Or are we likely to have an storage controller with an impending and critical fault?


We have a slightly confusing situation with a Smart Array P400 storage controller with the 512mb battery backed accelerator addon on an HP DL380 server.

The storage controller is (afaik) running the latest firmware and driver:

Model:  Smart Array P400 
Controller Status:  OK 
Firmware Version:  7.24 
Serial Number:  *snip* 
Rebuild Priority:  Medium 
Expand Priority:  Medium 
Number Of Ports:  2 

The storage diagnostic (both on the both boot-up screen for the controller and within the 'Management Homepage' and the 'HP Array Diagnostic Utility') recently starting showing the following status a fault for the battery for the accelerator:

Accelerator
Status:  Temporarily Disabled 
Error Code:  Cache Disabled Low Batteries 
Serial Number:  *snip* 
Total Memory:  524288 KB 
Read Cache:  25% 
Write Cache:  75% 
Battery Status:  Failed 
Read Errors:  0 
Write Errors:  0

We replaced the battery with a new unit (a visual inspection of the P400 card showing nothing unusual) and saw the same fault - but expected this to disappear over the course of a few hours/days as it charged. This didn't happen, and the fault status remains the same as above.

Given the battery is a genuine part from HP, I wouldn't have expected a replacement battery to fail straight away, or to be dead-on-arrival (is that naivety on my part?). Is the immediate failure of a replacement battery, for a failed battery, on a battery backed accelerator a common occurrence? Or are we likely to have an storage controller with an impending and critical fault? Is there any diagnostic that could tell me more about the failed battery, without cracking the server open again?

Many thanks!

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1 Answer 1

up vote 2 down vote accepted

You're correct. Firmware version 7.24 is the current release.

If you have the downtime window, power the server off entirely (remove power cables), wait a few minutes, and power up again. See if that jump-starts the battery charge process.

But short of that, if your system is still under warranty (P400-equipped systems went away in 2009), call for another battery unit. Sometimes HP technicians grab components from the wrong bin at the parts depot.

HP isn't in the battery business much anymore... The two most recent generations of HP Smart Array controllers can use flash-backed cache, which eliminate the impact of cough battery malfunction.

HP can analyze the battery status using a dump from the HP Array Diagnostic Utility (HPADU), but for a disposable part, it's better for everyone involved to just try a new unit.

Finally, if you're experiencing an unbearable drop in performance because of the dead battery, you can override the cache disablement. Look for the No-Battery Write Cache: Enabled option.

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Ah yes, I completely neglected to mention the performance impact (though it's well covered in the other P400 threads). Given the machine is doing a bit of everything we are certainly feeling the impacts of the lack of accelerator. Thanks for the pointers, particularly the No-Battery Write Cache option! –  inflammable Sep 11 '12 at 7:48
1  
A very small update to say that, as expected, the enabling the No-Battery Write Cache has restored the performance of the server. Workable for the time being. –  inflammable Sep 12 '12 at 9:32

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