Setting up Let's Encrypt with Nginx

Generate Diffie-Hellman parameters:

openssl dhparam -out /etc/ssl/certs/dhparam.pem 2048

Then uncomment ssl_dhparam /etc/ssl/certs/dhparam.pem in nginx configuration.

# sudo certbot certonly --dry-run
sudo certbot-auto --nginx -d DOMAINNAMEHERE