gistfile1.txt

server {
  location / {
    root /var/www/nginx-default;
    try_files /maintenance.html @frontends;
  }

  location @frontends {
    proxy_pass http://appservers;
  }
}

upstream appservers {
  server 127.0.0.1:8888;
  server 127.0.0.1:8889;
  server 127.0.0.1:8890;
}