// Note: The check method tries to listen on given port and closes it.
// It is possible to have a disconnected client in this tiny window of time.
func CheckPortAvailability(host, port string, opts TCPOptions) (err error) {
	lc := &net.ListenConfig{}

	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
	defer cancel()

	l, err := lc.Listen(ctx, "tcp", net.JoinHostPort(host, port))
	if err != nil {

    }

    upstream console {
        ip_hash;
        server minio1:9001;
        server minio2:9001;
        server minio3:9001;
        server minio4:9001;
    }

    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 console {
        ip_hash;
        server minio1:9001;
        server minio2:9001;
        server minio3:9001;
        server minio4:9001;
    }

    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.

			}
		}
	}
}

func getHosts(n int) (hosts []string, listeners []net.Listener, err error) {
	for range n {
		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)

    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.

	if runtime.GOOS != "linux" {
		t.Skip()
	}

	l, err := net.Listen("tcp", "localhost:0") // ask kernel for a free port.
	if err != nil {
		t.Fatal(err)
	}
	defer l.Close()

	port := l.Addr().(*net.TCPAddr).Port

	testCases := []struct {
		host        string
		port        int
		expectedErr error
	}{
		{"", port, fmt.Errorf("listen tcp :%v: bind: address already in use", port)},

		{"test-bucket-list-object", "", "", "", 5, resultCases[1], nil, true},
		{"test-bucket-list-object", "", "", "", 4, resultCases[2], nil, true},
		{"test-bucket-list-object", "", "", "", 3, resultCases[3], nil, true},
		{"test-bucket-list-object", "", "", "", 1, resultCases[4], nil, true},
		// Testing with prefix (25-28).
		{"test-bucket-list-object", "new", "", "", 3, resultCases[5], nil, true},

    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.

 * 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