I used to have an old RSS feed setup on one of my sites, but have since removed it - due to the number of users accessing it. For whatever reason the number of hits to the RSS feed has brought down my site - by spiking my CPU usage to well over 100%.
Now my site is un-reachable so I've hone ahead and removed the old RSS feed. Now I'm getting about 20-25 GET requests to the URL every 5 seconds, which now return a 404.
TLDR; Site was taken down by users hitting an RSS feed, RSS feed no longer exists - but users are still hitting the RSS feed, can't access my site due to a 504 Time-Out. Not sure how to best proceed - other than blocking incoming GET requests.