server {
        listen 80 default_server;
        listen [::]:80 default_server;

        root /var/www/html;

        index index.html index.htm;

        server_name _;

        location /alpha {
           proxy_pass http://nginx_alpha/index.html;
        }

        location /bravo {
           proxy_pass http://nginx_bravo/index.html;
        }

        location / {
           try_files $uri $uri/ =404;
        }

}