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Dell PE2950 PERC 5/i "controller write policy changed to write through" alert

I have a customer with a PowerEdge 2950 who is reporting that he is receiving an error having to do with the PERC 5/i RAID controller: "The Controller WRITE POLICY HAS BEEN CHANGED TO WRITE THROUGH.: BATTERY 0 CONTROLLER 0.
The controller write policy has been changed to Write Back.: Battery 0 Controller 0
The virtual disk cache policy has changed.: Virtual Disk 0 (Virtual Disk 0) Controller 0 (PERC 5/i Integrated)
The controller write policy has been changed to Write Through.: Battery 0 Controller 0"
Is this anything significant or is it some kind of normal maintanance event status alert?
3 Solutions
Darius GhassemCommented:
Here is the information on the alert. The alert can be normal

Description: The controller write policy has been changed to Write Through.

Cause: The controller battery is unable to maintain cached data for the required period of time. For example, if the required period of time is 24 hours, then the battery is unable to maintain cached data for 24 hours. It is normal to receive this alert during the battery Learn cycle. This is because the Learn cycle discharges the battery before recharging it. When discharged, the battery cannot maintain cached data.

Action: Verify the health of the battery. If the battery is not healthy, then replace the battery pack.

Severity: Warning/Noncritical. See "Alert Severity Levels" for more information.

Clear Alert Number: None.

SNMP Trap Number: 1153. See "SNMP Support for Storage Management Alerts" for more information.

Seth SimmonsSr. Systems AdministratorCommented:
I would first update the firmware on the controller.  I had a similar issue where it was doing that.  Dell acknowledged it was a firmware issue.  In my case the error didn't go away and they replaced the perc battery.

Latest is 5.2.2-0072.  If you already have that version, I suggest getting the battery replaced.
First, this is what you want.  If the battery can't hold a charge, then you simply risk your data in event of a drive failure, and in some instances, you risk data on even an unrecoverable read error (in combination with other events relating to I/O queue).

Batteries don't last forever.  The correct thing to do is just replace the battery.  Since it is a PERC/5, then the system is ancient, and unless they bought the controller from a vendor within last few years and it had a fresh battery then take my word for it, the battery does need to be replaced.

Buy a replacement from Dell, because you are assured it will be fresh enough to hold a decent charge.  The only other safe source is one of the manufacturers, but that requires minimum order levels and even then they only make manufacturing runs for certain controllers every 6 months or so.   Get it from a retailer who doesn't move a lot of PERC equipment, or ebay, and you probably end up with a battery just as old as yours.
PowerEdgeTechIT ConsultantCommented:
You can confirm whether it is performing its "Learning Cycle" or if the battery is dead by checking your controller log from OMSA.
PhillyGeeAuthor Commented:
The customer's firmware is way out of date and the battery, I think, has never been replaced so, in addition to updating the firmware I also recommended they replace the battery.
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