Cloudflare ssl does not working

[erictung]

I assume that your SSL encryption mode is Full or Full (strict).

Full or Full (strict) mode contacts your web server via port 443, but port 443 is not open in the server, hence the Error 521.

Community Tip - Fixing Error 521: Web server is down

Error Try the suggestions in this Community Tip to help you fix Error 521: Web server is down. Background A 521 error happens when we are unable to make a TCP connection to your origin server. Specifically, Cloudflare tried to connect to your origin server on port 80 or 443, but received a connection refused error. This is often caused by security or firewall software and happens if the origin server has directly refused Cloudflare’s proxy request. [Banner in tip catalog] Quick Fix Ideas …

Configure your web server to accept HTTPS traffic via port 443 with a valid SSL certificate, then proceed with Full (strict) SSL mode.