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DBO
Level 9
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Message 1 of 4

Critical Alert: Battery relearn

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One of our IronMail server (6.7.2) start sending this email message recently:

At: Thu, 25 Aug 2011 13:00:02

Host: localhost

Service: CUSTOM

Cause: CRITICAL

Info: DmesgWatch Alert: > mfi0: 6776 (367606675s/0x0008/info) - Battery relearn will start in 2 day

What is this Bettery Relearn alarm?  I found something here.  Should I cedule a restart of the server off-peak time?

http://yo61.com/dell-drac-bbu-auto-learn-tests-kill-disk-performance.html

I have also found this:

http://download.intel.com/support/motherboards/server/s7000fc4ur/sb/raidaccessoryaxxrsbbu4_tps_1_0.p...

Ce message a été modifié par: DBO on 25/08/11 12:31:15 CDT
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ijahnke
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Re: Critical Alert: Battery relearn

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The battery Learn cycle discharges and then fully charges the controller battery.

The Learn cycle recalibrates the battery integrated circuit so that the controller can determine whether the battery can maintain the controller cache for the prescribed period of time in the event of a power loss. For example, some controller batteries are required to maintain the controller cache for 72 hours.

While the Learn cycle is in progress, the battery may not be able to maintain the cache during a power loss. If the controller is using write-back cache policy, then the controller changes to write-through cache policy until the Learn cycle completes. The write-through cache policy writes the data directly to the disk and reduces the risk that data can be lost in the cache if there is a power loss.

You do not need to reboot the appliance as it will recharge on its own and should only take a few minutes

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ijahnke
Level 11
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Re: Critical Alert: Battery relearn

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The battery Learn cycle discharges and then fully charges the controller battery.

The Learn cycle recalibrates the battery integrated circuit so that the controller can determine whether the battery can maintain the controller cache for the prescribed period of time in the event of a power loss. For example, some controller batteries are required to maintain the controller cache for 72 hours.

While the Learn cycle is in progress, the battery may not be able to maintain the cache during a power loss. If the controller is using write-back cache policy, then the controller changes to write-through cache policy until the Learn cycle completes. The write-through cache policy writes the data directly to the disk and reduces the risk that data can be lost in the cache if there is a power loss.

You do not need to reboot the appliance as it will recharge on its own and should only take a few minutes

Re: Critical Alert: Battery relearn

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Also, according to the data in the alert, the relearn will occur on the weekend anyway, which I would expect to be off peak.

DBO
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Re: Critical Alert: Battery relearn

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Thank you all