Acer Network Device Altos R520 - Manual (Page 92)

3 System upgrade 82
Installing and removing the SAS
hardware RAID components
The system supports SAS hardware RAID through the active mid-plane
and backplane board. The server platform supports SAS hardware RAID
0, 1, 5, 6 (when available), 10, and 50 levels. Functionality for SAS
hardware RAID is enabled by using the following components:
• RAID activation key and RAID cache
The RAID activation key works in conjunction with the RAID cache
to provide hardware RAID.
• RAID BBU
If power to the storage I/O processor drops below specifications,
the RAID BBU maintains the contents of the DIMM by keeping the
DIMM in self-refresh mode until power is restored. After power is
restored, data can be safely written to drives, maintaining the
integrity of the disk array.
Installing and removing the RAID activation key
and RAID cache
To install the RAID activation key and RAID cache:
1 Observe the ESD precautions and pre-installation instructions
described on page 39.
2 Remove the power distribution board cover. Perform the
instructions described in “To remove a power distribution module
cover” section on page 48.
3 Remove the RAID activation key from its protective packaging.
4 Align then insert the activation key into the RAID activation key
connector on the active mid-plane board (A).
5 Locate the RAID cache memory (DDR-2) slot on the active
mid-plane board.