Replacing the Disk Controller Batteries

The disk controllers in storage servers and compute servers have battery-backed write cache to accelerate write performance. If the battery charge capacity degrades, so that the battery cannot protect the cached data for a power loss of 48 hours or more, then the write cache is disabled and the disk controller switches to write-through mode. Write performance is reduced, but no data is lost.

The battery charge capacity degrades over time, and its life expectancy is inversely proportional to the operating temperature. Table 13-1 shows the worst case life expectancy of a battery in Recovery Appliance.

Table 13-1 Battery Life Expectancy

Inlet Ambient Temperature Battery Lifetime

< 25 degrees Celsius (77 degrees Fahrenheit)

3 years

< 32 degrees Celsius (89.6 digresses Fahrenheit)

2 years

Monitoring Batteries in the Compute Servers

To monitor the battery change capacity in the compute servers:

# /opt/MegaRAID/MegaCli/MegaCli64 -AdpBbuCmd -a0 | grep "Full Charge" -A5 | sort \
| grep Full -A1

The following is an example of the output from the command:

Full Charge Capacity: 1357 mAh
Max Error: 2 %

You should proactively replace batteries that have a capacity less than 800 milliampere hour (mAh) and a maximum error less than 10%. Immediately replace any battery that has less than 674 mAh or a maximum error greater than 10%.

To monitor the battery temperature:

/opt/MegaRAID/MegaCli/MegaCli64 -AdpBbuCmd -a0 | grep BatteryType; \
/opt/MegaRAID/MegaCli/MegaCli64 -AdpBbuCmd -a0 | grep -i temper

The following is an example of the output from the command:

BatteryType: iBBU08
Temperature: 38 C
  Temperature                  : OK
  Over Temperature        : No

If the battery temperature is greater than or equal to 55 degrees Celsius, then determine the cause, and correct the problem.

Note:

Storage servers generate an alert when the battery charge capacity is insufficient, the temperature is high, or the battery should be replaced.

Replacing Batteries in Disk Controllers

Oracle replaces the failed batteries at no extra charge under these conditions:

  • The battery charge capacity in the disk controllers falls below the minimum threshold

  • The system is covered either by the Oracle Premier Support for Systems or occurs during the warranty period.

For customers with Premier Support for Systems, Oracle attempts to proactively replace the batteries in Recovery Appliance before the end of the estimated lifetime, on a best effort basis.