Chapter 5: Subsystem Maintenance and Upgrading

Step 7. Reinstall the controller module. After the DIMM module has been properly installed, install the RAID controller. To do this, align the controller module with the controller module bay. Then gently push the controller module in the controller bay. Carefully push the controller until you feel the contact when the board edge connectors are being mated to the backplane. Do not use force. If unusual contact resistance is felt, try it again. Use the ejection levers on the sides of the controller to secure it into the chassis.

When the controller is inserted with the lever at its the lowest position, notches on the levers should properly clinch to the round metal protrusions on the interior walls of module bay. You may then pull the lever upward to secure the controller into module bay.

Step 8. Next secure the controller module into the subsystem by fastening the screws through holes underneath each ejection lever.

5.4. Replacing a Faulty BBU

The BBU is an optional item for the subsystem that can sustain cache memory in the event of a power failure or in the unlikely event of failing both PSUs. The BBU provides additional data security and helps minimize the chance of losing data due to power outages.

A BBU consists of a metal bracket, battery cell pack, and a PCB board that connects to the controller module. Each BBU is secured to the subsystem using retention screws. Please read the BBU handling precautions below before proceeding with the replacement procedure.

Fault Conditions:

A BBU failure can result from the following:

1.A BBU has lost its ability to hold electrical charge. This may be the case after the battery cells have been recharged for many times regardless of how long the module has been used. Therefore, a stable power source is important for system operation.

2.The charger circuitry implemented with the controller has failed.

There are other conditions that might trigger the BBU fault events and trigger the BBU fault LED:

1.The temperature sensor embedded with the subsystem’s charger circuit reports a temperature reading exceeding the preset threshold. The charger circuits will enter a low-power and self-protection state.

Replacing a Faulty BBU

5-9