"The Dell Server RAID user guide seems to suggest there can be more than one virtual disk on an array." Where do you see this?  (Technically, an "array" is a "virtual disk" (VD).)  The SAS 6/iR lists support for 2 VD's, but does not list anything about the number of VD's "per disk group".  Higher-end PERC controllers list, as part of their specs, the number of totally supported VD's, as well as the number of VD's per disk group; as the SAS 6/iR does not list this, I would assume that this cannot be done, and that while it is capable of 2 VD's, it is limited to a single VD per disk group.  I have also never seen this done in all my years of working with Dell servers. To better utilize your your 500GB disks, the way to do what you are wanting to do is to backup, delete VD, configure VD, restore.
Running Windows SBS 2008 on 3 partitions (1 OS, 2 Data, 3 Data) on a SAS 6/ir controller RAID1 Integrated Mirroring Virtual Disk This array appears as 'Virtual disk 0' within Dell OpenManage Server Application The physical disks are currently one 250gb and one 500gb drives.  Virtual disk 0 is only 233gb. Question: By removing the 250gb drive and replacing with another 500gb drive and then syncing the array, will I have the option to create a new Virtual disk in the remaining space? The Dell Server RAID user guide seems to suggest there can be more than one virtual disk on an array. If this is possible I'd like to move the data partitions to 'Virtual disk 1' and then expand the first partition across the original data partitions on 'Virtual disk 0'. Could anyone who understands what I mean here confirm whether or not it is possible/advisable.  I do have a good third party backup solution to rely on as 'plan b'. MTIA     
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