I think I have a setting problem with Fail2ban apache-badbot filter because I unfortunately have attacks of this type, and Fail2ban does not ban any IP. //

failregex = ^<HOST> -[^"]*"(?:GET|POST|HEAD) \/.* HTTP\/\d(?:\.\d+)" \d+ \d+ "[^"]*" "[^"]*(?:%(badbots)s|%(badbotscustom)s)[^"]*"$

Fail2ban has a build-in tool for testing the fail2ban filters, called fail2ban-regex, which you can use via command line. Like:

fail2ban-regex /var/www/vhosts/<your domain>/logs/access_ssl_log /etc/fail2ban/filter.d/apache-badbots.conf

Once you're happy with the matched results, then use the following (replacing the last value with the name of your jail) to commit the changes without having to restart the Fail2Ban service:

 fail2ban-client reload nameofyourjail