A configuration option available for any that is configured to use .
When asynchronous write mode is selected, any write requests to the are completed by the , without waiting for an I/O completion indication from the secondary storage array that the data was successfully copied.
As a result of selecting this , write requests are not guaranteed to be completed in the same order on the as they on the primary virtual disk. If the order of write requests is not preserved, data on the secondary virtual disk may become inconsistent with the data on the primary virtual disk, which would jeopardize any attempt to recover data if a disaster occurs on the primary .
The Preserve consistent write order option enables you to preserve the order, while retaining the performance benefits obtained with the asynchronous write mode. If a new write request to the primary virtual disk attempts to change data associated with a pending write request, the RAID controller module will place the incoming write request into a queue until the pending write has been completed.