errFatal(local.RegisterSingleHandler(handlerTest, h1))
	errFatal(local.RegisterStreamingHandler(handlerTest2, h2))

	// local to remote
	remoteConn := local.Connection(remoteHost)
	errFatal(remoteConn.WaitForConnect(context.Background()))
	const testPayload = "Hello Grid World!"

	gotResp := make(chan struct{})
	go func() {
		start := time.Now()
		t.Log("Roundtrip: sending request")

		res.Mux = append(res.Mux, m)
	}
	xioutil.SafeClose(ready)
	for _, m := range res.Managers {
		for _, remote := range m.Targets() {
			if err := m.Connection(remote).WaitForConnect(ctx); err != nil {
				return nil, err
			}
		}
	}
	return &res, nil
}

// Cleanup will clean up the test grid.
func (t *TestGrid) Cleanup() {
	t.cancel()
	t.cleanupOnce.Do(func() {

}

// WaitForConnect will block until a connection has been established or
// the context is canceled, in which case the context error is returned.
func (c *Connection) WaitForConnect(ctx context.Context) error {
	if debugPrint {
		fmt.Println(c.Local, "->", c.Remote, "WaitForConnect")
		defer fmt.Println(c.Local, "->", c.Remote, "WaitForConnect done")
	}
	c.connChange.L.Lock()

		t.Log("2: server payload: ", len(payload), "bytes.")
		err := RemoteErr(payload)
		return nil, &err
	}))

	// local to remote
	remoteConn := local.Connection(remoteHost)
	remoteConn.WaitForConnect(context.Background())
	defer testlogger.T.SetErrorTB(t)()

	t.Run("localToRemote", func(t *testing.T) {
		const testPayload = "Hello Grid World!"

		start := time.Now()