A. In a previous FAQ, I described how if you want to defragment a volume, you can't have other nodes in the cluster performing direct access. You need to place the CSV into redirected access mode, where all I/O is performed by the coordinator node.

For a third party disk defragmentation tool to support CSV, it must perform the defragmentation on the coordinator node, turn on redirected access, defragment the CSV, then place the CSV back in direct access mode.

I performed some testing and spoke to Diskeeper. Diskeeper 2009 fully supports CSV by performing the calls to place the CSV in redirected access mode and performing the defragmentation on the coordinator node for the CSV.

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