I have been using OMV for a 30TB NAS for a few years now. I have always been able to index it with Spotlight before, and use Spotlight/Alfred to search it. My feeling (although I can't remember exactly) is that I was able to use Spotlight with both SMB and AFP as I have them both turned on for various users and have connected both ways.
An OSX revision or two just before Catalina, and Spotlight searches have stopped working on the OMV server. I have literally spent dozens of hours on this problem, reading articles, searching the internet to no avail.
The index appears to be created. It shows that it's indexing, I can find the index manually in the terminal. mdutil shows that indexing is enabled and everything LOOKS normal, however spotlight cannot find any files on the OMV server.
Anybody have any insight? I have a ton of business documents on this server and not being able to pull them up quickly is driving me crazy.