Issuing a Free HTTPS SSL Certificate with Let's Encrypt

sudo apt install -y certbot python3-certbot-nginx

sudo certbot --nginx -d example.com -d www.example.com

sudo certbot certonly --nginx -d example.com

server {
    listen 443 ssl http2;
    server_name example.com;

    ssl_certificate     /etc/letsencrypt/live/example.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem;

    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256;
    ssl_prefer_server_ciphers off;
    ssl_session_cache shared:SSL:10m;
    ssl_stapling on;
    ssl_stapling_verify on;

    location / {
        proxy_pass http://127.0.0.1:3000;
    }
}

server {
    listen 80;
    server_name example.com;
    return 301 https://$host$request_uri;
}

systemctl status certbot.timer
sudo certbot renew --dry-run

sudo certbot certonly \
  --manual \
  --preferred-challenges dns \
  -d "*.example.com" \
  -d example.com