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Fail2Ban
Scans log files and check for in appropriate password activities and update and uses firewall (IPTables) to restrict (stop for a period of time) these activities. So fail2ban limits incorrect authorisation attempts, thereby reducing, but not entirely eliminating associated risks and bandwidths. It is primarily used on port and associated services open to the public. DigitalOcean How To Protect an Apache Server with Fail2Ban on Ubuntu 14.04 and How Fail2Ban Works to Protect Services on a Linux Server. Also see the wiki of Fail2Ban on nftables and Fail2ban Add support for nftables #1118 and Add nftables actions #1292.