Converting fully allocated VDisks

You can convert fully allocated VDisks to space-efficient VDisks.

You can nondisruptively convert a fully allocated VDisk into a space-efficient VDisk by following this procedure:

Start with a single copy, fully allocated VDisk.
Add a space-efficient copy to the VDisk. Use a small real capacity and the autoexpand feature.
Wait while the VDisk mirroring feature synchronizes the copies.
Remove the fully allocated copy from the space-efficient VDisk.

Any grains of the fully allocated VDisk that contain all zeros do not cause any real capacity to be allocated on the space-efficient copy. Before you create the mirrored copy, you can fill the free capacity on the VDisk with a file that contains all zeros.