Help! Added drives to R720xd/H710 mini but OS cannot mount them


New Member
Mar 11, 2019
Last night I had the brilliant idea of adding some nearly full 3.5" drives to my R720xd/H710 mini. I hit CTRL+R after boot screen, added the Virtual Disks one at a time as single RAID 0 VDs. I did not check the initialize box as these drives already have data on them. I installed Debian 10 on an SSD and could see the 3.5" drives when partitioning, but only installed the OS on the SSD. I full-upgraded to Sid and all seemed well. I went to Disks and can see all of the 3.5" drives (9 drives, mix of 8TB and 4TB) but when I go to mount the drives I get the following error:

Error mounting filesystem. 
Error mounting /dev/sdX at /media/username/WDC-8GB-01: wrong fs type, bad option, bad superblock
on /dev/sdX, missing codepage or helper program, or other error (udisks-error-quark, 0)
There are a mix of drives that were formatted ext4 and some zfs ( I will not be using ZFS on these drives and will likely wipe them.)
Any advice on how to access the data on these drives or did I screw up big time and accept that I messed up the data on the drives? At this time, I only have one empty/unformatted 8TB drive that has not been attached to the 720xd yet if that matters for backup/restore of disk or partition images.

Also, if I flashed the H710 mini to IT Mode (thanks @fodeesha) what would I have to do to remove the disks from the virtual drives? If I removed the Physical disks from the Virtual Disks then flash the H710 mini to IT mode and used the disks in passthrough, would that work?