Howto error 521 after getting DNS valid, SSL library error

Website, Application, Performance Security
4

It looks like canman.ee is grey-clouded right now, so we can test the origin’s connection:

➜  ~ nc -zv canman.ee 80
nc: connectx to canman.ee port 80 (tcp) failed: Connection refused
➜  ~ nc -zv canman.ee 443
Connection to canman.ee port 443 [tcp/https] succeeded!

It looks like port 443 (HTTPS) is working just fine and Port 80 is closed. If you are seeing HTTP 521 that implies perhaps Cloudflare is using your HTTP port incorrectly - check your SSL setting on Cloudflare and choose Full Strict SSL:

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