错误：无法在截止日期前连接 URL：grpc://localhost:7051

:~/Documents/test/education/LFS171x/fabric-material/tuna-app/$ node query.js 
Store path:/home/*******/Documents/test/education/LFS171x/fabric-material/tuna-app/hfc-key-store
Successfully loaded user1 from persistence
2020-02-11T05:56:10.423Z - error: [Remote.js]: Error: Failed to connect before the deadline URL:grpc://localhost:7051
Query has completed, checking results
error from query =  Error: Failed to connect before the deadline URL:grpc://localhost:7051
    at checkState (/home/******/Documents/test/education/LFS171x/fabric-material/tuna-app/node_modules/fabric-client/node_modules/grpc/src/client.js:883:16) {
  connectFailed: true
}

我正在尝试 Hyperledger Fabric，使用这个链接 http://websecuritypatterns.com/blogs/2017/12/15/exploring-hyperledger-fabric-v1-supply-chain-demo-tuna-fish-shipments/以供参考，

使用registerAdmin.js和registerUser.js成功注册管理员和用户。 我目前在运行后遇到此错误节点查询.js.

我需要帮助解决此错误，

错误：在截止日期之前无法连接 网址：grpc://localhost:7051。

平台：Ubuntu 18.04， 使用本地环境试验超级账本结构。

提前致谢。