SUPER MICRO Computer AOC-USAS-L4i - Manual (Page 26)

3-10
Add-on Card User's Guide
3. Use the arrow key to select Off or On for Disk WC (DWC) or Read Ahead.
4. When you see the prompt Change DWC or Change Read Ahead, use the arrow
key to select Off or On, then press Enter to change the cache setting.
The settings are changed for all logical drives defined on the array.
3-4 Rebuilding a Drive
The MegaRAID BIOS CU enables you to rebuild a drive of a redundant array if the
array has a failed drive. If the failed drive is still good (that is, if the drive is physi-
cally present and its size is greater than or equal to the defined size of the array) it
will be rebuilt. If the drive is small, an error message will appear and the MegaRAID
BIOS CU will not allow the drive to be rebuilt. A rebuild cannot be started on a failed
drive if its size is even 1 byte smaller than the defined size of the array.
Follow these steps to rebuild a drive:
1. Select Rebuild from the Management Menu.
2. When the list of drives appears, highlight the FAIL drive that you want to rebuild
and press the Spacebar to select it.
3. After selecting the physical drive, press F10 and select Yes at the confirmation
prompt.
The rebuild process begins, and a graph shows the progress of the rebuild until it
is complete. Although the CU changes the disk drive state to Rebuild at this point,
the change does not appear on the screen while the rebuild is in progress. If the
CU detects a media error on the source drive during rebuild, it initiates a sector
read for that block. If the sector read fails, the CU adds entries to the Soft Bad
Block Management (SBBM) table, writes this table to the target drive, and displays
an error message. Additional error messages are displayed if the SBBM table is
80% full or 100% full. If the SBBM table is completely full, the rebuild operation is
aborted, and the drive is marked as FAIL.