Issues with LiteSpeed Recaptcha

[TommyTran732]

Hi,

I am having some issues with LiteSpeed recaptcha. I am currently using Xenforo 2, Plesk, LiteSpeed Enterprise (via the LiteSpeed addon) and my website runs behind Cloudflare Pro.

Recently, I have ran into some issues with DDOS attacks and these bots seem to bypass my firewall on Cloudflare, so I want to have a captcha turned on when my server is under high load. My settings are as follows:







I did set up access control for cloudflare's IP and set Use Client IP in Header to Trusted IP Only. My issue is, under a DDOS attack, the captcha shows up, loads extremely slowly, then reloads, then gives me a 503 error. The server's resources, however, are far from being saturated. Everything seems to be in good condition, but I somehow get a frozen screen with the captcha and the error.



I wonder if there is a way to fix this?

Thank you

 

[mistwang]

Using cloudflare as front-end proxy make it much more difficult to really stop the botnet, as everything is going through CloudFlare, server cannot stop accepting requests from it, including those from botnet.
My suggestion is to bypass cloudflare in such case, see if it can defeat the attack.