# If they come here using HTTP, bounce them to the correct scheme
# Nginx internal code used for the plain HTTP requests 
# that are sent to HTTPS port to distinguish it from 4XX in a log and an error page redirection.
error_page 497 https://$host$request_uri;

# Increase keepalive connection lifetime
keepalive_timeout	70;
keepalive_requests	150;

# SSL encryption parameters
ssl_protocols TLSv1.2 TLSv1.3;
ssl_ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384;
ssl_prefer_server_ciphers off;

ssl_certificate		/etc/nginx/ssl/cert.pem;
ssl_certificate_key	/etc/nginx/ssl/cert.pem;
ssl_dhparam         /etc/nginx/ssl/dhparam.pem;

# performance
ssl_session_cache	shared:SSL:10m;
ssl_session_timeout	10m;