I have not bveen able to use Rockstor for 18 months now because it wont install on my later hardware. It isnt the fault of Rockstor per-se but that fact that its based on a 2015 Centos version which itself will not install on modern hardware.
Rockstor 3.9 is based off of Centos 7.x, just with Linux Kernel 4.12 instead of 3.10. So as long as your hardware is supported in Linux Kernel 4.12, it should work with Rockstor.
The problem isn’t the kernel its the installer amd I have tested this ad-nauseam with vanilla centos. The Rockstor release and below <=1511)of centos just will not install on later uefi hardware. Its as simple as that. As a result I have never been able to use the Rockstor I bought once I gor my dedicated low power motherboard.
What hardware have you been trying to install on? As well as what exactly is the issue you are seeing? Some details (errors, steps, etc…) would be good. In order to help you, you must first help us.