This morning, Maker Forums Discourse responded to me with a “429” error — too many requests — even though I hadn’t been making any requests. I found a web crawler making many requests to the site and temporarily firewalled it to bring Maker Forums back while investigating.
I discovered that a configuration change I made while moving to the new server three months ago, on 21 December 2022, caused the site’s rate limits to be applied to all traffic together, instead of being restricted to the source of the problematic traffic.
I have, I believe, repaired this configuration, and I have restored access for the affected web crawler.
If, in the future, you encounter a “429 Too Many Requests” error when you are not madly clicking through Maker Forums, opening dozens of tabs at once, please comment in this thread with the exact time (including time zone) that the problem occurred to you, to make it possible to investigate.