Controller cache preservation – Dell PowerEdge RAID Controller H700 User Manual

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Storage Controller Features

Automatic Replace Member with Predicted Failure

A Replace Member operation can occur when there is a SMART predictive

failure reporting on a physical disk in a virtual disk. The automatic Replace

Member is initiated when the first SMART error occurs on a physical disk

that is part of a virtual disk. The target disk needs to be a hot spare that

qualifies as a rebuild disk. The physical disk with the SMART error is marked

as failed only after the successful completion of the Replace Member. This

avoids putting the array in degraded status.
If an automatic Replace Member occurs using a source disk that was

originally a hot spare (that was used in a rebuild), and a new disk added for

the Replace Member operation as the target disk, the hot spare reverts to the

hot spare state after a successful Replace Member operation.

NOTE:

To enable the automatic Replace Member, use the Dell OpenManage

storage management application. For more information on automatic Replace

NOTE:

For information on manual Replace Member, see "Replacing an Online

Controller Cache Preservation

The controller is capable of preserving its cache in the event of a system

power outage or improper system shutdown. The PERC H700 controllers are

attached to a Battery Backup Unit (BBU) that provides backup power during

system power loss to preserve the controller's cache data. The PERC H800 has

a transportable version of the BBU attached to it called the Transportable

Battery Backup Unit (TBBU) which enables the entire cache module to be

transported to a new controller if necessary. If the card has the optional non-

volatile cache (NVC) or transportable non-volatile cache (TNVC) module,

the cache data is preserved using flash storage instead of battery power.

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