[zimpenfish]

But it also helps in reducing the load on your servers when, e.g., instead of 300+ login attempts per minute on your mail ports, you get 20 because the IP gets banned for a day after 2 failures. Or, instead of nginx spending 90% of its time sending out 404s for the various PHP and MySQL holes I do not have installed, it can spend 10% of its time instead.

Particularly on my small server, fail2ban is the difference between "usable" and "on the edge of falling over".

[dizhn]

Parent says there are more robust solutions to these and there are. Rate limiting is one that has been in use forever for example.

[zimpenfish]

Yes, I'm rate-limiting by using fail2ban to drop traffic that I don't want.