The last version our our source code, the tar.gz files, that compile/are compatible with a CentOS base, such as is used in our near legacy v3 variant, was 3.9.2-57. There after we ran into a python library issue in CentOS and our dependency on it. But we were well on the way to our v4 “Built on openSUSE” variant by then. We have also since then released our DIY installer solution for v4 in the following repository:
which is linked to, and recommended for new installs, at our downloads page on the main web site:
https://rockstor.com/download.html
This is currently your first port-of-call to build your own installer. It will, as a consequence our the method we use (kiwi-ng), end up pre-loaded with all pending upstream updates. In other words the day you build you installer it will include all openSUSE distributed updates. The rpm version of Rockstor installed will currently be 4.0.8-0 (I changed this yesterday and updated the download page to have this newly released version as the recommended on.
We intend to make pre-build downloads available once we release our next official Stable release. But given 4.0.8-0 is Release Candidate 9 and we have now sorted the docker/Rock-on issue things are looking positive for 4.0.8-0 being our next Stable release. So there’s that 
.
So in short, for now, you need to follow the instructions in the above GitHub repo to build your own “Built on openSUSE” Rockstor 4.0.8-0 version. It can in turn subscribe to testing or stable just as before and can import config and pools just as the CentOS one did.
We released CentOS and “Built on openSUSE” versions for a goodly while during this transition and had intended to continue this until re reached the next stable version. But allas our own tecnical dept and that of CentOS combined to defeat this goal. So as from 3.9.7-57 we could only release rpms (what the new installer auto includes/uses) that run on that openSUSE Leap base.
There are now may folks on the forum who have successfully built their own installer using that GitHub repos instructions and feedback on making it easier/clearer is welcomed. The instructions themselves have now undergone quite a few enhancements and as of just the other day it is now possible to build the installer using any relatively modern linux install. Our prior, and now secondary method, within the instructions required a Leap 15.2 instance, either ‘real’ or virtual within say a virtual machine. But as of a recent contribution from @kageurufu here on the forum, answering a long stand request within the Readme, we now have the far easier and more flexible boxbuild method which does the KVM (virtual machine) stand-up/setup for you on the fly.
Try building your own installer and report on your findings. It’s long winded computationally but only a few command on a modern linux install. We are very keen on having this build-you-own / DIY installer approach being well known and accessible as in the previous years of our attempting to release installers as often as possible and ‘gold stamping’ them they were almost always out of date the day they were released. This new DIY way, in keeping with our more technical audience (DIY NAS builders who install their own OS) ensures that each install build has all pending updates pre-installed. This makes for a far faster stand-up and also means folks start out on the latest kernel / btrfs updates form the get go.
In time we hope to arrange for an auto-build installers arrangement with the consequent download made available but this, as stated, is not planned until we are at the next stable release. All in good time and bit by bit.
Let us know how you get on with the new installer. There are 14 months worth of updates on all sides between 3.9.2-60 and 4.0.8-0. I mentioned 3.9.2-60 specifically due to it’s inclusion of a potential fix for your reported issue. But you also want all inbetween fixes ideally. Plus there’s that several years newer kernel and btrfs stuff that is key to your experiments that comes with the move from our CentOS base with elrepo kernel 4.12, to the bang up to date (with backports) Leap kernels and openSUSE/SLES’s backports specifically of the btrfs. CentOS never really did this hence our use of the elrepo kernel. That was all way more hacky than what we now do in the v4 (which actually started work in the 3.9.* eara. See the beginning of the following thread for some background:
and it’s pre-cursor:
But your next port-of-call to test our modern offering is the GitHub repo with the instructions on how to build you own installer with all updates pre-installed; and specifically it’s README.md:
https://github.com/rockstor/rockstor-installer#readme
Have a read, and a go, and report any difficulties in a new forum thread. The hopefully those with experience in this process can chip in and get you sorted. You will then, there after, be able to easily build a fully updated installer on-the-spot. This is particularly useful for getting a fresh, fully updated install off-to-the-races as it were.
Hope that helps.