My clients in The Netherlands (connecting to servers in The Netherlands) suddenly get random 521 errors from Hamburg. All my servers are online. Why is traffic from NL routed via DE? What causes these random 521 errors?
521 errors usually refer to your origin server being down/unresponsive
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
…
https://support.cloudflare.com/hc/en-us/articles/115003011431-Troubleshooting-Cloudflare-5XX-errors#521error
My mistake, my fail2ban-client somehow blocked some of CF’s IPs.
system
February 11, 2020, 9:33am
4
This topic was automatically closed after 14 days. New replies are no longer allowed.