Replicate with iSCSI

Hi,

I have two ReadyNAS Pro 4's with Replicate installed on both, using 4x1.5TB drives. The source NAS has 2 iSCSI drives on it as well as 3 regular shares. The iSCSI drives are 1TB and 2TB in size, although almost nothing is actually in them currently. The reason for using iSCSI is because Windows Server 2008R2 won't use non-local storage for backups or file serving, hence iSCSI gets around that by presenting apparently local drives.

I ran my first "system backup" job on Friday and it looks like the Replicate software sees the iSCSI drives as big blocks which need to be backed up in their entirety. Does this mean that the iSCSI drives don't fit well into the Replicate framework, and if so can I use the "backup data" option to do things more sensibly? The free space remaining on the target drive indicates 3TB has been used, which isn't at all desirable. I added one 64KB file to one of the iSCSI drives and set off another "system backup" job and it looks like it's starting from scratch; when I relocate the target drive offsite (which is the whole point of this type of backup for us) it will take something like 2 years to complete a backup!

Thanks,

Jeremy