I have a couple of samba shares that I want to be included in Spotlight/ Alfred search results so I did
sudo mdutil -i on /Volumes/together
to turn on indexing of that share (and the same with some other shares). I understand that indexing takes time so I waited a couple of days but I’m still not getting any results from any of those SMB shares.
I am on an M1 mini with Big Sur and on my previous M1 mini I somehow did manage to get those shares indexed (although the results were somewhat unreliable/slow to update, but that’s another issue) so I know it is possible, but I don’t understand how.
Edit: I now remembered that I also had to add those shares to the search scope in Alfred (Preferences → Features → Default Results), so I did that and 
Alfred now finds the files on my network drives. But Spotlight doesn’t (which is weird, as I thought that Alfred uses Spotlight).
So I think that was how far I got on my previous Mac. But I’d still like to understand how to get Spotlight to find those files too.