Cloudflare | Free Online Tutorials

CentOS 7: use certbot to register SSL certificate for multiple domains with Cloudflare

phptuts June 9, 2022

Install certbot Step 1-5: CentOS 7: install certbot to register wildcard SSL certificate Using certbot to register SSL certificate for multiple domains Step 6: Confirm…

Lua / Openresty: How to get real client IP address

phptuts May 4, 2022

Supports CloudFlare, Incapsula, Sucuri, Any Proxy … Note: if you use reverse proxy, you should use: Test: Online demo: http://5.161.72.222/test/ip

PHP check if page is accessed with HTTPS

phptuts September 4, 2021

This code supports Cloudflare:

How to fix error in WordPress: redirected you too many times

phptuts May 5, 2019

How to fix error in WordPress: redirected you too many times This error orcurs when you use CloudFlare with SSL. Simple: add some lines in…

DDOS protection with Nginx and Cloudflare

phptuts December 24, 2018

Method 1: Step 1: Get all IP range of cloudflare: https://www.cloudflare.com/ips-v4 and https://www.cloudflare.com/ips-v6 You see: and Step 2: Config Nginx Method 2: Config Nginx:

How to fix Error 521: Web server is down with HTTPS website using Cloudflare

phptuts December 14, 2018

Sometime you see a strange error: your website run with HTTP but with HTTPS you get error 521, how to fix this error? Step 1:…

How does CloudFlare DDOS protection work?

phptuts March 19, 2016

New version: How does CloudFlare DDOS protection work? – Update 09/2016 I went to some website and saw the CloudFlare DDOS protection, pictured below: I…

Using IPv6 with Cloudflare

phptuts November 13, 2015

Step 1: Go to Add site Fill this input with your root domain (not subdomain) and click Begin Scan. Wait for a few seconds Then,…