If your traffic runs through a proxy service like Cloudflare or Fastly, all incoming traffic is using their IPs. When fail2ban blocks a brute force attack, it uses these IP addresses, which can cause valid users to get blocked as well!
WP Fail2ban supports adding proxy IP addresses to its configuration and will inspect the X-Forwarded-For header on requests in this case.
This plugin automatically updates WP Fail2ban’s configuration with the published IP addresses for popular proxy services so that WP Fail2ban plays nicely with them. When those services update their IP ranges, the plugin automatically fetches them.
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