Gregory's Server@Gargron thank you for your quick answer. Unfortunately it looks like I need a straight forward instruction :) I can already start Nginx with some adjustments suggested by you, but there is still something wrong configured. My second instance is showing partially content of the first one.
Should I ask this question on https://github.com/tootsuite/mastodon ?
@drsebro Look, here, hopefully this illustrates what I'm talking about enough:
https://gist.github.com/Gargron/590b84aa766ce32c0bc7f004f27c52b1
Also, if you're not using Docker, you should know how to isolate your two servers from each other: Use different DB_NAME, use REDIS_NAMESPACE, and if using local filestorage for uploads, make sure they don't write to the same directory.