The data I have been working on migrating is being done as disk images. I create a disk image file of the same size as the volumes on the zpool (rounded up to the nearest 5GB), format as ext4, mount, then rsync the files over on the Linux box locally to the mounted images. Then after I unmount them, from Windows I copy them over to the Drobo. The one problem I keep having though is that the images are coming up as too small, and I have to rebuild them all over again and start the process over. It's very time consuming. I'm starting to think I should have created a zpool on the zpool and just added more images to it as needed to satisfy the needs of the export. I'm doing all of this because for some reason, zfs won't let me replace a failing disk with a brand new disk.