NGINX Configuration for WordPress Multisite + Domain Mapping with HTTPS

nginx.conf

server {
  listen 80;
  listen [::]:80;
  server_name example.com www.example.com subsite.com www.subsite.com another.com www.another.com;
  return 301 https://$host$request_uri;
}

server {
  listen 443 ssl http2;
  listen [::]:443 ssl http2;

  server_name example.com www.example.com subsite.com www.subsite.com another.com www.another.com;

  ssl on;
  ssl_certificate /etc/letsencrypt/live/example.com/fullchain.pem;
  ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem;
  ssl_stapling on;
  ssl_stapling_verify on;
  ssl_trusted_certificate /etc/letsencrypt/live/example.com/chain.pem;
  
  ssl_protocols TLSv1.1 TLSv1.2 TLSv1.3;
  ssl_session_cache shared:SSL:20m;
  ssl_session_timeout 10m;
  ssl_prefer_server_ciphers on;
  ssl_ciphers 'ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-SHA384:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-RSA-AES256-SHA:!aNULL:!eNULL:!EXPORT';
  ssl_dhparam /etc/ssl/dhparam.pem;
  
  add_header X-Frame-Options SAMEORIGIN;
  add_header X-Content-Type-Options nosniff;
  add_header X-XSS-Protection "1; mode=block";
  add_header Strict-Transport-Security "max-age=31536000; includeSubDomains; preload";
	
  access_log /var/log/nginx/example.com.access.log rt_cache;
  error_log /var/log/nginx/example.com.error.log;

  root /var/www/example.com/htdocs;
  index index.php index.html index.htm;
	
  # WordPress nginx config rules
  include common/php.conf;
  include common/wpsubdir.conf;
  include common/wpcommon.conf;
  include common/locations.conf;
  # Custom nginx.conf
  include /var/www/example.com/conf/nginx/*.conf;
}