fritex
February 24, 2021, 9:07pm
2
Have you tried looking for a fix here?https://support.cloudflare.com/hc/en-us/articles/115003011431-Troubleshooting-Cloudflare-5XX-errors#521error
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
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Moreover, do you have an valid SSL certificate at your origin/host for your domain and your sub-domains? Also, which SSL mode have you got enabled (Full SSL, …)?
If not, write back to us
