Disk Cache Battery

What is a Disk Cache Battery?

A RAID disk controller is a system fail-safe feature that allows for a disk in a disk array to fail without bringing the system down.

Built into the RAID controller is a cache. The cache tells the processor that the data write-to-disk is complete, so the system knows to go back to the processor to fetch more data to send to the disks.

This cache has a battery to keep the data in the cache safe until it gets written to the disk drives.

What Happens When This Battery Fails?

As this battery loses power, you will get a warning message on your console to call your service provider.

When it fails completely, the system turns off the caching function of the disk controller.

Your data is NEVER at risk but, because caching is turned off, system performance will be noticeably degraded.