After a little more review of the source - I think I want to take the DVA (Data Virtual Address - which consists of a vdev / offset combination) and force all the vdevs to always resolve to vdev2 on writes (rather than vdev1).
Later, I can go back and try to add an attribute to a vdev which will disallow it to be written to during DVA. Any thoughts or insights on this approach are most welcome, ~Mike -- This message posted from opensolaris.org