HP Surestore Disk Array 12h - And FC60 Advanced User's Manual page 303

Enabling Disk Write Cache Enable (WCE)
WCE should only be enabled in environments that provide uninterruptible
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AUTION
power to the disk array. A loss of power to the disk array may result in data
loss with WCE enabled.
If maximum I/O performance is critical, disk WCE can be enabled on all the disks in the
array. Disk WCE enhances disk array I/O performance, but increases the possibility of data
loss during a power loss.
If WCE is enabled, this procedure for enabling disk WCE should be executed any time a
disk module is replaced or a new disk module is added to the array. This will ensure that
WCE is enabled on all disks in the array.
To enable WCE on all disks, type:
amutil -w on <ArrayID>
WCE will be enabled on all disks visible to the array controllers. Depending on the number
of disk modules in the array, this command can take up to 60 seconds to complete.
Command Example
The following example enables WCE on all disks in disk array ARRAY1:
amutil -w on ARRAY1
Managing the Disk Array Using Array Manager 60
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