@attis Thanks for debugging, I added a new config setting into config.json, you can set isCluster: true in your config.json and it should work now. It will be available in 1.9.2 so you can keep your change until then. https://github.com/NodeBB/NodeBB/issues/6509
From my understanding, Redis keeps the entire forum database in memory?...so if the forum gets large, it sounds like that scales very poorly.
Second the latter part of attis's question. I've set up a trial nodeBB using what I think is "just mongo" and I've seen "just redis" tutorials as well. How do you do this Redis+Mongo mixed setup, and when does that become worth it over just Mongo for a larger board?