upstream minio {
        server minio1:9000;
        server minio2:9000;
        server minio3:9000;
        server minio4:9000;
    }

    # main minio
    server {
        listen       9000;
        listen  [::]:9000;
        server_name  localhost;

         # To allow special characters in headers
         ignore_invalid_headers off;
         # Allow any size file to be uploaded.

    upstream minio {
        server site1-minio1:9000;
        server site1-minio2:9000;
        server site1-minio3:9000;
        server site1-minio4:9000;
    }

    server {
        listen       9001;
        listen  [::]:9001;
        server_name  localhost;

        # To allow special characters in headers
        ignore_invalid_headers off;
        # Allow any size file to be uploaded.

    upstream minio {
        server site2-minio1:9000;
        server site2-minio2:9000;
        server site2-minio3:9000;
        server site2-minio4:9000;
    }

    server {
        listen       9002;
        listen  [::]:9002;
        server_name  localhost;

        # To allow special characters in headers
        ignore_invalid_headers off;
        # Allow any size file to be uploaded.

	if port <= 0 {
		return
	}
	mux := http.NewServeMux()
	var listener net.Listener
	var err error
	if listener, err = net.Listen("tcp", fmt.Sprintf(":%d", port)); err != nil {
		log.Errorf("unable to listen on socket: %v", err)
		return
	}
	exporter, err := monitoring.RegisterPrometheusExporter(nil, nil)
	if err != nil {
		log.Errorf("could not set up prometheus exporter: %v", err)

		log.Warnf("Failed to create directory for %v: %v", path, err)
	}

	var err error
	listener, err := net.Listen("unix", path)
	if err != nil {
		return nil, fmt.Errorf("failed to listen on unix socket %q: %v", path, err)
	}

	// Update file permission so that cni plugin has permission to access it.
	if _, err := os.Stat(path); err != nil {

		}
	}
}

func getHosts(n int) (hosts []string, listeners []net.Listener, err error) {
	for i := 0; i < n; i++ {
		l, err := net.Listen("tcp", "127.0.0.1:0")
		if err != nil {
			if l, err = net.Listen("tcp6", "[::1]:0"); err != nil {
				return nil, nil, fmt.Errorf("httptest: failed to listen on a port: %v", err)
			}
		}
		addr := l.Addr()
		hosts = append(hosts, "http://"+addr.String())
		listeners = append(listeners, l)

 * shared resources.
 *
 * @param <K> the most general type of keys this listener can listen for; for example {@code Object}
 *     if any key is acceptable
 * @param <V> the most general type of values this listener can listen for; for example {@code
 *     Object} if any key is acceptable
 * @author Charles Fry
 * @since 10.0
 */
@GwtCompatible

 * shared resources.
 *
 * @param <K> the most general type of keys this listener can listen for; for example {@code Object}
 *     if any key is acceptable
 * @param <V> the most general type of values this listener can listen for; for example {@code
 *     Object} if any key is acceptable
 * @author Charles Fry
 * @since 10.0
 */
@GwtCompatible
@FunctionalInterface

	listenCfg := net.ListenConfig{
		Control: setTCPParametersFn(opts),
	}

	for i, serverAddr := range serverAddrs {
		l, e := listenCfg.Listen(ctx, "tcp", serverAddr)
		if e != nil {
			if opts.Trace != nil {
				opts.Trace(fmt.Sprint("listenCfg.Listen: ", e))
			}

			listenErrs[i] = e
			continue
		}

		if opts.Trace != nil {
			opts.Trace(fmt.Sprint("adding listener to ", l.Addr()))

  --name etcd-gcr-v3.3.9 \
  gcr.io/etcd-development/etcd:v3.3.9 \
  /usr/local/bin/etcd \
  --name s1 \
  --data-dir /etcd-data \
  --listen-client-urls http://0.0.0.0:2379 \
  --advertise-client-urls http://0.0.0.0:2379 \
  --listen-peer-urls http://0.0.0.0:2380 \
  --initial-advertise-peer-urls http://0.0.0.0:2380 \
  --initial-cluster s1=http://0.0.0.0:2380 \
  --initial-cluster-token tkn \