User guide

Viewing Battery Information
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Viewing Battery Information
The Battery Backup Unit (BBU) is an add-on card that can be attached to
most 3ware 9000 RAID controllers to supply power from a battery pack in the
event of a system power loss. (The BBU is not supported on the 9590SE-
4ME.) 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.
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 211.
To view information about a BBU in 3BM
• At the main 3BM screen, tab to the Information button and press Enter.
On the pop-up menu, select Battery Backup 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 211.
Testing Battery Capacity
Batteries in the BBU need to be replaced periodically. A battery test should be
run every four weeks in order to get a reliable estimate of battery capacity, and
to determine when it needs to be replaced.
The battery test is used to measure the battery’s capacity to back up write data.
In order to make a reliable estimate of battery capacity, the BBU pre-charges
the battery before it proceeds with a full discharge cycle. The battery is
Note: When the BBU status is not “Ready,” write caching is automatically disabled
on all units attached to the controller