robots.txt – Disallow well-behaved crawlers from accessing specific directories:

User-agent: *
Disallow: /private/
Firewall/WAF rules – Use services such as Cloudflare or your hosting firewall to block known bot IPs and suspicious traffic.
CAPTCHA challenges – Require CAPTCHA verification on forms and sensitive pages.
Rate limiting – Restrict the number of requests from a single IP within a given time period.
Block specific user agents – Configure your web server (.htaccess, Nginx, etc.) to deny requests from unwanted bots.
Bot management tools – Use advanced bot detection services that analyze behavior rather than just user-agent strings.

In my experience, the best approach is to combine a few security measures rather than relying on a single plugin. A service like Cloudflare can help filter suspicious traffic before it reaches your website, while rate limiting can reduce repeated requests from abusive bots. You can also check your server logs to identify common IP addresses and user-agent patterns. Just be careful with blanket IP or country blocking, as it may affect genuine visitors too. The robots.txt file is useful for guiding legitimate crawlers, but malicious bots can ignore it. If you're using WordPress, reviewing your CIDRAM settings and keeping plugins updated is also worth considering.