Indeed we do have such infrastructure in place for the hosted version of Sharetribe Go. Such situation happens all the time, it takes quite some time and resource to manage bots and spam!
This is really specific to your own infrastructure. I’m not sure if DigitalOcean offer such service, out of the box, but maybe you could check with them?
Possibly other open-source users will share their own scripts and rules to manage such bad trafic on their own server, so that you can be inspired for your own.
Hmm usually that information is gathered directly from your logs or infrastructure (and you can build rules like “if attempt to log in x times in m minutes then block for d day”).
You can at least find the login IP in the people table, for each logged in user, but this won’t help too much with bots who are trying to sign up. For that, monitoring traffic and logs is the best way to go.