brute-force

Fail2ban filters to slow SSH and application abuse

Fail2ban is not a complete defense, but it is a useful friction layer for noisy abuse. I use it where login failures or repeated 401s clearly indicate hostile automation. It works best when paired with centralized logs and upstream rate limiting, not

Rate limiting abusive clients with Rack::Attack

Rate limiting is both a security control and an availability control. I use it to slow credential stuffing, login brute force, and noisy scraping without punishing normal use. The trick is keying limits on the right dimensions and emitting metrics so