@softraid-support: Yep, I'm having the same issue described above. Initially Big Sur was backing up fine to my pre-existing four HDD SoftRAID (RAID 5, 30TB) over eSATA just fine. When I upgraded my network to 10GB and therefore built a new SoftRAID (this time 1+0 RAID, 20TB to get a speed boost), System Preferences got stuck at "Preparing Backup" for >24 hours and I decided to force-quit.
In the meantime, my solution is to trick Time Machine by connecting to a local Time Machine share (a smb Time Machine share folder which resides on my local SoftRaid RAID 1+0) Volume: This can be done by creating a loopback network interface alias (for example '127.0.0.100' that points to 'lo0'. That way I can connect via smb to the local Time Machine share using smb://127.0.0.100. Time Machine will recognize it as a network Time Machine destination.
There's actually some beauty in that: Now my local Mac Pro server Time Machine backup is in a .sparsebundle along with all the other Macs backed up to that shared folder.
@softraid-support I have the same issue with time machine. It hangs when you select the disk for time machine. It get stuck to “preparing disk” with a halfway progress bar.
@kurt Hi, how do you creat both apfs volume and softraid volume on a single disk? I have 2x12tb and 2x10tb running on raid5 and wanted to utilised the remaining 4tb in the 2x12tb for time machine. Thanks.
Time Machine under Big Sur requires APFS. That is why it is hanging.
I think you are creating a RAID 0 or 1 for the Time Machine? then you can use this beta.
http://www.softraid.com/sr_beta
Create the volume and select APFS as the file system.
@softraid-support Just tried it but will not allow me to format the volume as APFS since it is part of a disk which is in my Raid5. I guess I have to wait until softraid volume can again be use by time machine. After 59 days will my softraid version revert to 6.0.3?
Wait until next week, when 6.0.4 is released, then use the release version.
@softraid-support My mistake, I upgraded the driver but was still using the 6.0.3 application. That is why there is no APFS in the volume format. Just manage to successfully format part of the disk that I'm using as Raid 5 to APFS and Time Machine is now up and running. Thank you very much, Excellent!!!