Using a Digital Ocean LEMP Ubuntu 16.04 installation with one site example.com. Visting http://example.com works normally.
Installed Let's Encrypt using https://www.digitalocean.com/community/tutorials/how-to-secure-nginx-with-let-s-encrypt-on-ubuntu-16-04 successfully without running into any errors.
When visiting https://example.com the browser says, "example.com refused to connect."
What is the best steps to diagnosis Let's Encrypt issues when not seeing any errors?
To note, in /var/etc/nginx/sites-available/ there is "default" and "digitalocean". Default has "www.example.com and example.com" in it. But do not see any lines in regards to Let's Encrypt before or after installation. I had thought the LE install would update that config with LE lines. No changes to "digitalocean" config either. Don't see any errors in /var/log/nginx/error.log.
When running, "sudo lsof -iTCP -sTCP:LISTEN -P" It mentions items listening on 22 and 80 but none say 443. Running "sudo ufw status" shows 443 allow and "443 (v6)", "Nginx Full (v6)" etc.
Wondering if someone can recommend how to start diagnosing the issue?
UPDATE: Reverted to snapshot before installing and tried again. This time noticed one new error: "Cannot find a VirtualHost matching domain example.com. In order for Certbot to correctly perform the challenge please add a corresponding server_name directive to your nginx configuration: https://nginx.org/en/docs/http/server_names.html"
That would clearly cause the issue, but in /etc/nginx/sites-available/default "server_name example.com www.example.com;" are there and as noted the http site loads without a problem. Is there a reason why Let's Encrypt can't see that?