In a storage device, the write policy of LUNs in a RAID group is set to Write Back; however, the physical read/write performance of services is low and cannot meet the standard specifications of the device.
Product and version information:
In the ISM, choose Fault > Fault Management, and the alarm message BBU Is Faulty can be found under Faults List.
Reinsert or replace the BBU module.
In the ISM, unfold All RAID Groups under the Logical tab.
Select a LUN in the RAID group and right-click it to select Modify LUN, and then set the Write Strategy to Write Back for the LUN.
Log in to the ISM.
Choose Fault > Fault Management, and the Fault Management window is displayed.
The alarm message BBU Is Faulty can be found under Faults List.
The storage device automatically sets the write policy of LUNs to Write Through when the BBU module is faulty, deteriorating the read/write performance.
This operation may lead to data loss when a storage device is powered off abnormally.
If you fail to recover the faulty BBU and want to improve the read/write performance immediately, please try to set Write Strategy to Write Back Mandatory for the LUN.