Cache battery pack

Use this procedure to service the cache battery pack.

1. Cache battery pack replacement procedure information

   Attention: To prevent possible data loss, ensure that the cache battery pack is in an error state before replacing it. This will ensure all cache data is written to disk and that it is safe to replace the cache battery pack. By following this procedure, you are going to: Force the cache battery pack into an error state. Perform the cache battery pack replacement. You will be allowed to resume this procedure later if you cannot ensure that the cache battery pack is in an error state. Forcing the cache battery pack into an error state will result in the following: The system logs an error. Data caching becomes disabled on the selected controller. System performance could become significantly degraded until the cache battery pack is replaced on the selected controller. The battery pack can be safely replaced field on the controller rechargeable battery information screen will show Yes. The cache data present LED will stop flashing. The cache battery pack requires replacement. Ensure that you have the correct type of cache battery pack to perform the replacement.

   If you have powered the machine off, power it on before you continue.

2. Select the operating system:
   AIX®	Linux	IBM® i
   ↓	Go to step 7.	Go to step 5.

3. Force the cache battery pack into an error state using the AIX operating system

   To force the cache battery pack into an error state in order to prevent possible data loss, proceed as follows on the system or partition containing the adapter: Navigate to the IBM SAS Disk Array Manager as described below: At the command prompt, type smit, and press Enter. Select Devices. Select Disk Array. Select IBM SAS Disk Array. Select IBM SAS Disk Array Manager from the menu with options for configuring and managing the IBM SAS RAID Controller. Select Diagnostics and Recovery Options. Select Controller Rechargeable Battery Maintenance. Select Force Controller Rechargeable Battery Error. Select the IBM SAS RAID Controller whose battery you want to replace, using this option places the battery into the error state, which requires it to be replaced. Press Enter. Determine that it is safe to replace the cache battery pack. Refer to How to display rechargeable battery information below. It is safe to replace the cache battery pack when Yes is displayed next to Battery pack can be safely replaced. You may need to reselect the option to Display Controller Rechargeable Battery Information multiple times as it may take several minutes before it is safe to replace the cache battery pack. How to display rechargeable battery information Navigate to the IBM SAS Disk Array Manager as described above. Select Diagnostics and Recovery Options. Select Controller Rechargeable Battery Maintenance. Select Display Controller Rechargeable Battery Information. Select the IBM SAS RAID Controller.

4. Go to step 8.

5. Force the cache battery pack into an error state using the IBM i operating system

   To force the cache battery pack into an error state in order to prevent possible data loss, proceed as follows on the system or partition containing the adapter: Be sure that you are signed on to the system with at least service level authority. Type strsst on the command line and press Enter. Type your service tools userid and service tools password on the System Service Tools (SST) Sign On display. Press Enter. Select Start a Service Tool from the System Service Tools (SST) display. Press Enter. Select Hardware Service Manager from the Start a Service Tool display. Press Enter. Select Work with resources containing cache battery packs from the Hardware Service Manager display. Press Enter. Select Force battery pack into error state for the I/O card you are working with from the Work with Resources containing cache battery packs display. Press Enter. On the Force Battery Packs Into Error State display, verify that the correct I/O adapter has been selected and press the function key that confirms your choice. Return to the Work with Resources containing cache battery packs display and select Display battery information. Ensure that the field Safe to replace cache battery = YES. Note: This may take several minutes and you may need to press the refresh key to see the field update.

6. Go to step 8.

7. Force the cache battery pack into an error state using the Linux operating system

   To force the cache battery pack into an error state in order to prevent possible data loss, proceed as follows on the system or partition containing the adapter: Run the iprconfig utility by typing iprconfig. Select Work with disk unit recovery. Select Work with resources containing cache battery packs. Select your adapter and type 2. Then press Enter to force the battery error. Note: Using this option places the battery into the error state, which requires it to be replaced. If you are sure you want to force a battery error, type c to confirm. If you do not want to force a battery error, type q to cancel. Determine that it is safe to replace the cache battery pack. Refer to How to display rechargeable battery information below. It is safe to replace the cache battery pack when Yes is displayed next to Battery pack can be safely replaced. You may need to reselect the option to Display Controller Rechargeable Battery Information multiple times as it may take several minutes before it is safe to replace the cache battery pack. How to display rechargeable battery information Run the iprconfig utility by typing iprconfig. Select Work with disk unit recovery. Select Work with resources containing cache battery packs. Select your adapter and type 1. Then press Enter to display battery information.

8. Place into service position

   Note to expansion unit users: The instructions in this procedure are written based on the rack model. Expansion unit users can still use this procedure. However, users of expansion units should ignore specific references to rack-only features, such as rack doors, rack thumbscrews, and rack-specific FRU orientation. Open the front rack door. Identify the system unit you are servicing in the rack. Remove the two screws (A) (if present) that secure the system unit (B) to the rack.

9. Place into service position (continued)

   Notes: When placing the system into the service position, it is essential that all stability plates are firmly in position to prevent the rack from toppling. Ensure that only one system unit is in the service position at a time. Ensure that the cables at the back of the system unit do not catch or bind as you pull the unit forward in the rack. When the system unit rails are fully extended, the rail safety latches lock into place. This action prevents the system from being pulled out too far. While holding the system unit release latches (A) down on both the left and right sides, pull the system unit (B) out from the rack until the rails are fully extended and locked.

10. Remove the service access cover

    Loosen the two thumbscrews (A) located at the back of the cover. Slide the cover (B) toward the back of the system unit. When the front of the service access cover has cleared the upper frame ledge, lift the cover up and off the system unit. Attention: For proper cooling and air flow, re-install the cover before turning on the system. Operating the system without the cover for more than 30 minutes could damage the system components.

11. Check cache data present LED

    Examine the LED (A) near the cache battery pack on the RAID enablement card. This LED is called the cache data present LED. If the LED is flashing, there is cache data that has not been written to disk. If the LED is not flashing, all cache data has been written to disk.

    Is the cache battery LED flashing?
    Yes, the LED is flashing	No, the LED is not flashing
    ↓	Go to step 13

12. Stop removing the cache battery pack

    Attention: The flashing LED indicates that there is cache data that has not been written to disk. This data will be lost if the battery is removed at this time. Do not replace the cache battery pack at this time. Complete this service procedure without replacing the cache battery pack, then retry it to ensure all cache data is saved before the battery is replaced

    Go to step 15.

13. Remove the cache battery pack

    Attention: Do not remove battery if LED (C) is flashing; cache data exists. While applying pressure downward on the card to ensure that it remains seated, move the cache battery lever (A) away from the connector to disengage the battery from the connector. Slide the cache battery pack (B) out of the mounting guides and remove it from the controller.

14. Install the cache battery pack

    Attention: When installing the cache battery pack, ensure that the cache battery pack is disconnected for at least 60 seconds before connecting the new battery. This is the minimum amount of time needed for the card to recognize that the battery has been replaced. Slide the cache battery pack (B) into the mounting guides on the controller until it is seated in the battery connector (C). Move the lever (A) to the latched position to fully seat the battery into the connector.

15. Install the service access cover

    Place the service access cover (A) on top of the system, about 25 mm (1 in.) from the upper chassis ledge. Hold the service access cover against the system unit and slide it toward the front of the system. The tabs of the service access cover slide beneath the upper chassis ledge. Align the two thumbscrews (B) located on the back of the service access cover with the two holes on the back of the system chassis. Tighten the thumbscrews to secure the service access cover.

16. Place into operating position

    Note: When placing the system into operating position, ensure that the cables at the back of the system do not catch or bind as you push the system unit back into the rack. Unlock the rail safety latches (B) by sliding them toward the front of the system. Push the system unit (A) back into the rack until both system-unit release latches have locked into position.

17. Place into operating position (continued)

    Replace and tighten the two screws (B) that secure the system unit (A) to the rack. Close the front rack door of the unit you are servicing.

18. Close the back door

    Close the back rack door on the unit you are servicing.

19. Was the cache battery LED flashing during steps 11 and 12 of this procedure?
    Yes, the LED was flashing. Do not restart the adapter's write cache.	No, the LED was not flashing. Restart the adapter's write cache.
    Go to step 2 or contact your next level of support.	Continue with the next step.

20. Restart the adapter's write cache by doing the following steps:

    Select your operating system:

    AIX: Go to step 21. Linux: Go to step 22. IBM i: Go to step 23

21. Perform the following steps:

    Navigate to the IBM SAS Disk Array Manager by using the information in step 3a. Select Diagnostics and Recovery Options. Select Controller Rechargeable Battery Maintenance. Select Start Adapter Cache. Select the controller with the battery you just replaced and press Enter. Go to Verifying a repair.

22. Perform the following steps:

    Run the iprconfig utility by typing iprconfig. Select Work with disk unit recovery. Select Work with resources containing cache battery packs. Start the I/O adapter cache on the adapter for the battery that you just replaced by typing 3 and press Enter. Go to Verifying a repair.

23. Perform the following steps:

    Return to the Work with Resources containing Cache Battery Packs display using the information in step 7a to 7f and select the Start IOA cache. Press Enter. Ensure that you get the message Cache was started. Go to Verifying a repair.