socketFactory[ipv6] = server1.inetSocketAddress
    socketFactory[ipv4] = server2.inetSocketAddress

    client =
      client.newBuilder()
        .fastFallback(false)
        .apply {
          retryOnConnectionFailure = false
        }
        .build()

    executeSynchronously(request)
      .assertFailureMatches("stream was reset: REFUSED_STREAM")

    assertThat(client.routeDatabase.failedRoutes).isEmpty()

              socketConnectTimeoutMillis = socketConnectTimeoutMillis,
              socketReadTimeoutMillis = socketReadTimeoutMillis,
              pingIntervalMillis = pingIntervalMillis,
              retryOnConnectionFailure = retryOnConnectionFailure,
              fastFallback = fastFallback,
              address = address,
              routeDatabase = routeDatabase,
              connectionUser = user,
            ),
          ),

      socketConnectTimeoutMillis = chain.connectTimeoutMillis,
      socketReadTimeoutMillis = chain.readTimeoutMillis,
      pingIntervalMillis = client.pingIntervalMillis,
      retryOnConnectionFailure = client.retryOnConnectionFailure,
      fastFallback = client.fastFallback,
      address = address,
      routeDatabase = client.routeDatabase,
      connectionUser =
        CallConnectionUser(
          call,

     * calling application should do its own recovery of connectivity failures.
     */
    fun retryOnConnectionFailure(retryOnConnectionFailure: Boolean) =
      apply {
        this.retryOnConnectionFailure = retryOnConnectionFailure
      }

    /**
     * Configure this client to perform fast fallbacks by attempting multiple connections

      socketConnectTimeoutMillis = socketConnectTimeoutMillis,
      socketReadTimeoutMillis = socketReadTimeoutMillis,
      pingIntervalMillis = pingIntervalMillis,
      retryOnConnectionFailure = retryOnConnectionFailure,
      user = user,
      routePlanner = routePlanner,
      route = route,
      routes = routes,
      attempt = attempt,
      tunnelRequest = tunnelRequest,

    e: IOException,
    call: RealCall,
    userRequest: Request,
    requestSendStarted: Boolean,
  ): Boolean {
    // The application layer has forbidden retries.
    if (!client.retryOnConnectionFailure) return false

    // We can't send the request body again.
    if (requestSendStarted && requestIsOneShot(e, userRequest)) return false

    // This exception is fatal.

      socketConnectTimeoutMillis = socketConnectTimeoutMillis,
      socketReadTimeoutMillis = socketReadTimeoutMillis,
      pingIntervalMillis = pingIntervalMillis,
      retryOnConnectionFailure = retryOnConnectionFailure,
      user = connectionUser,
      routePlanner = this,
      route = route,
      routes = routes,
      attempt = 0,
      tunnelRequest = tunnelRequest,
      connectionSpecIndex = -1,

          socketConnectTimeoutMillis = chain.connectTimeoutMillis,
          socketReadTimeoutMillis = chain.readTimeoutMillis,
          pingIntervalMillis = client.pingIntervalMillis,
          retryOnConnectionFailure = client.retryOnConnectionFailure,
          fastFallback = client.fastFallback,
          address = client.address(request.url),
          connectionUser = CallConnectionUser(this, connectionPool.connectionListener, chain),

    val dns: Dns = client.dns()
    val followSslRedirects: Boolean = client.followSslRedirects()
    val followRedirects: Boolean = client.followRedirects()
    val retryOnConnectionFailure: Boolean = client.retryOnConnectionFailure()
    val callTimeoutMillis: Int = client.callTimeoutMillis()
    val connectTimeoutMillis: Int = client.connectTimeoutMillis()
    val readTimeoutMillis: Int = client.readTimeoutMillis()

   eventListenerFactory, followRedirects, followSslRedirects, hostnameVerifier, interceptors,
   networkInterceptors, pingIntervalMillis, protocols, proxy, proxyAuthenticator, proxySelector,
   readTimeoutMillis, retryOnConnectionFailure, socketFactory, sslSocketFactory, writeTimeoutMillis
 * **PushPromise**: headers, method, path, response
 * **Request**: body, cacheControl, headers, method, url