docs: private boolean sendReq(List<Node> monitorNodes, HttpCmd cmd) {
          while (true) {
              Node node = selectMNode(monitorNodes);
              try {
                  cmd.setNodeIdentity(node.getIdentity());
                  HttpCmdResponse response = HttpCmdClient.doPost(node.getIp(), node.getPort(), cmd);
                  if (response.isSuccess()) {
                      if (LOGGER.isDebugEnabled()) {
                          LOGGER.debug("Report Monitor Data Success.");
                      }
                      return true;
                  } else {
                      LOGGER.warn("Report Monitor Data Failed: " + response.getMsg());
                      monitorNodes.remove(node);
                  }
              } catch (Exception e) {
                  LOGGER.warn("Report Monitor Data Error: " + e.getMessage(), e);
                  // 重试下一个
              }
              if (monitorNodes.size() == 0) {
                  return false;
              }
          }
      }