The following fragment will pick one server at a time. Is there a way to hit them all at once?

```
upstream backend {
    server 17.0.0.1:8000;
    server 17.0.0.1:8001;
    server 17.0.0.1:8002;
    server 17.0.0.1:8003;

}

server {
    location / {
        proxy_pass http://backend;
    }
}

```