LH 6000 - failure BBU

[CA957027]

Since yesterday we have some problem with our LH6000 Netserver.
There is shown a failure in the HP Instant Top TOOLS, but we don't know the right voltage.

The data of the failure:

Code 202 - Voltage sensor BBU voltage crossed the lower critical threshold.
The reading of the BBU-Voltage is 2.34 Volts.

Our first question is, where we can find this BBU-voltage and the second, how an we solve the voltage.

## I hope you know what we meen ##
thanks and greetings from germany
Lenz

[CA845876]

This error is coming from the battery backup unit for your embedded NetRAID. The usual voltage is about 5 volts, but I don't know what the threshold is that qualifies it as low.

Assuming that you have a free standing (tower) unit, look at the unit from the front, then take off the plastic bezel. Remove the metal panel.

Near the back of the left side of the unit, should be a blue plastic battery pack about 10 cm X 10 cm (I'm only guessing at the size, here) mounted to the chassis. This will be connected to a PC board by a cable with perhaps 10 or 12 conductors to it (I'm guessing, again). This is the battery backup (BBU).

The NetRAID subsystem generates the error. This error does NOT threaten the normal operation of your server, UNLESS power is lost. The battery's sole purpose is to maintain the disk cache of the NetRAID in case of unanticipated power failure.

I have also heard stories of this being a false error on batteries that are actually good, and of the error happening when the server gets really hot inside. I don't know if you're running in a very warm environment or not.

What you might try is simply unplugging the server from the AC mains, then unplugging the battery cable, waiting two minutes, and then reversing the process. I have heard rumors that this is sometimes a false error, and will go away if you do this. I don't know why.

If you have a voltmeter, you could check the battery directly. Look for about 5.0 volts. If it shows 3.6 volts, probably one of the cells is shorted; the pack needs to be replaced.

Of course, if you're under warranty, call HP and make them replace the pack, anyway.