AMCC 3ware 9000 Series, User Manual

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Maintaining Your Controller
156 3ware 9000 Series Serial ATA RAID Controller User Guide
If units are present, you should see unit information in the system
log (usually,
/var/log/messages
).
6
If you wish to load the driver automatically every time
the system is rebooted,
add the line
'twa_load="YES"'
to the
file
/boot/loader.conf
Viewing Battery Information
The Battery Backup Unit (BBU) is an add-on card that can be attached to a
3ware 9000 RAID controller to supply power from a battery pack in the event
of a system power loss. This allows the controller to use write-caching for
optimal performance and to preserve data in the event of a system power
failure. When fully charged, the battery preserves the contents of the cache
memory for up to 72 hours. When power is restored, the cached write data is
written to the disks.
Note:
When the BBU status is not “Ready,” write caching is
automatically disabled on all units attached to the controller.
You can see information about a battery backup unit attached to your
controller in both 3DM 2 and 3BM.
To view information about a BBU in 3DM 2
„
On the menu bar, choose Monitor > Battery Backup .
The Battery Backup Page appears, on which you can see details and status
about the unit. This page is refreshed every 30 seconds.
For details about the fields on this page, see “Battery Backup Page” on
page 68.
To view information about a BBU in 3BM
„ At the main 3BM screen, tab to the BBU button and press Enter .
The Battery Backup Unit screen appears.
The fields on this screen are the same as those available through 3DM.
For details about the fields, see “Battery Backup Page” on page 68.