SoftRAID is a bit different than UnRAID. UnRAID is more a direct competitor of NAS providers or Drobo. I say Drobo because UnRAID similarly will let you mix and match drives. It is typically deployed on dedicated storage servers, so like a NAS or DROBO. However, it is a “proprietary” implementation like Drobo’s. I quote “proprietary” because I’m uncertain as to whether either of them have actually invented something or if they are just doing their own implementation of approaches which are in the literature. Both UnRAID and DROBO provide greater flexibility than standard RAID but at the same time they do not have the robustness or industrial strength of something like ZFS. Note, ZFS is actually much more flexible, but also can be even more complex. Even so, I really was hoping for Apple to do something like ZFS. As it is APFS is mostly doing things which were common in storage management appliances in the mid 1990s.
SoftRAID is firmly a Mac solution with a relatively long history on the Mac. Since 1996 they have been a provider of Software based RAID solutions for the Mac platform. They provide drivers which are deployed in macOS and enhance its capabilities. SoftRAID is not meant to be primarily a dedicated storage device. SoftRAID doesn’t offer all flavours of RAID. Currently, they only offer RAID 0, 1, 4, 5, and 1+0. So no RAID 6, which I too would prefer. Sometime in the past few years they were acquired by Other World Computing / MacSales and are providing the software for OWC’s Thunderbolt RAID solutions for the Mac.
The remainder of this is a long story as to why I became a somewhat loyal customer. No need to read, unless you wish to hear the story. I’m in no way associated with SoftRAID.
SoftRAID did bail me out at one point in a work situation where another manufacturers hardware failed and that manufacturer wouldn’t in any way stand behind their product because it was out of its one year warranty period. I don’t want to dump on anyone so no names, other than they are a brand name storage provider which has a long history with the Mac and were in Apple Stores from the beginning.
This is around 2001 and in those days for lower cost external storage we were using things like firewire 800. I STUPIDLY built a larger RAID 0 stripe volume with something like seven drives using the unnamed manufacturers drives. Note I say drives but that is really a misnomer since the drives were produced by someone like Western Digital or Seagate. The brand name company was just providing cabinet, limited RAID capability within the electronics of the cabinet, and a power supply. In any event, I had a very important work product on a RAID 0 volume and just after the work was done, but before I could move it someplace else one of the disks in the RAID 0 volume failed.
It was the brand name company’s drive which failed but they were not willing to do a thing because the drives were a little over a year old. SoftRAID on the other hand stepped up and held my hand through the process of getting it working. As it turned out the drives when removed from brand names box and put in a docking station would work. However, they were a bit garbled because of the electronics failure. SoftRAID provided me with terminal DD commands for dumping certain sectors from the effected drives and had me ship the file control data extracts to them. They then sent me DD commands to over write selected sectors to patch the drives with repaired file system data structure information. That all worked and I had a working RAID 0 volume from which I could extract the project which was on the failed and then resurrected RAID 0 volume.
I was very grateful to SoftRAID for helping me to recover from the brand name companies equipment failure. Also, through that effort I learned that the drives inside the brand name cabinet had a longer warranty if I bought them directly and they cost less. So from that point forward, I’ve only been buying raw drives. I probably have something like 40+ drives ranging in size from 500GB to now 8TB. I’m figuring 10TB helium filled drives are the next ones for my Mac Pro. A few years later, in a less dramatic scenario SoftRAID once again helped to debug and work around what was a bug in Apple HFS+. In general, my experience has been that they stand behind their products and support clients in resolving issues even when it is not their fault.
After the RAID 0 failure, even though SoftRAID saved my neck, I actually stopped using them for a while. I was a bit gun shy of external home grown RAID implementations and for a while only used Apple RAID. At one point I really wanted an Apple Xserve as my personal file server. But that was always out of my price range. However, as I needed larger volumes and Apple effectively stopped advancing their RAID solutions I eventually went back to using SoftRAID. Currently I have 32TB in three different SoftRAID volumes hanging off of my MacPro. I have had disk failures but I have always made it through the event with SoftRAID functioning in the manner it should.