I have a pool of 3x500GB where one the physical drives is having intermittent issues. Currently, there is only one parity Virtual Disk of 300GB Fixed across 3 columns. I want to replace the bad drive with a good one. The old way (pre-2012) was replace the disk, repair the RAID 5, resync and done. These basic steps are not working.
So far I have added a 4th 500GB drive to the pool. After searching and failing to find a way to move the data non-destructively, I decided to just pull the data cable on the disk I wanted to replace. After refresh/rescan, the disconnected drive shows "lost communication" and the virtual disk (after trying to repair) shows "unknown" (but the volume on that disk is accessible in Explorer). When I try to remove the physical disk in Server Manager, I get "The selected physical disk cannot be removed". Reading the error message, I see that the replacement disk cannot contain any part of a virtual disk. The replacement disk that I just added appears to have some space allocated (possibly because I have tried this same procedure a couple of times already?). When I look at the parity disk properties/health, it shows all four physical disks under "physical disks in use".
I have deleted and recreated a lot of storage pools lately while trying to understand how they work but I would like to avoid that this time. The data on the virtual disk in question is highly deduplicated and it took quite a while to get it that way. Since I can't find a way to copy/mirror the disk while keeping it fully deduplicated, I would need 3x the space to copy it all off, or a lot of time to load up and deduplicate a new virtual disk.
I have several questions:
1. How can a 3 column parity disk use parts of four physical disks? And can that be fixed without recreating the virtual disk?
2. When creating a virtual disk (for example a 3 column disk in a pool that has four or more physical drives), is there a way to specify which physical disks to use?
3. I understand that after a physical disk failure, the recovery process will move a virtual disk's allocation to a replacement disk, but can a virtual disk's allocation be moved manually among physical disks within the same storage pool
using a PS script?
4. Can a deduplicated virtual disk be moved/mirrored/backed up without expanding the data?
Any help is appreciated.