Docker connection error

[jhonclavijotro]

Hi, I'm new to Nginx and I've been having trouble creating a proxy for a domain on DuckDNS. I have an Arch Linux-based operating system, and this problem occurs when I try to access the domain after configuring the SSL certificate.
Can anyone suggest a solution?
mydomain.duckdns.org: There is a server found at this domain but it returned an unexpected status code Invalid domain or IP. Is it the NPM server? Please make sure your domain points to the IP where your NPM instance is running.

[Das-Rabindra]

It sounds like your DuckDNS domain is resolving to your server, but NPM is rejecting the request due to a domain validation issue.

Here are some things to check:

DuckDNS DNS Setup:
Make sure your DuckDNS domain (mydomain.duckdns.org) correctly points to the public IP address of the server running NPM.

Port Forwarding:
Ensure ports 80 and 443 are forwarded on your router to your NPM server's local IP.

NPM Proxy Host Configuration:

Confirm you added mydomain.duckdns.org as a proxy host domain in NPM.

Enable Block Common Exploits in the SSL tab for added security.

Enable Force SSL to redirect HTTP to HTTPS.

SSL Certificate:

If you’re using Let's Encrypt, make sure the certificate request completed successfully.

Check the logs inside NPM for certificate errors. Sometimes rate limits or DNS misconfiguration cause failures.

Validate NPM Instance IP:
If your server has multiple network interfaces or IP addresses, verify that NPM is listening on the IP your domain points to.

Test with curl:
From outside your network, run:

curl -v https://mydomain.duckdns.org