Cannot connect to Ethereum client using truffle/ganache

Question

I first started ganache and see in the log that "Ganache started successfully" with the RPC Server set as: HTTP://127.0.0.1:7545

While running truffle migrate command, I've received the following message:

Could not connect to your Ethereum client with the following parameters:
    - host       > 127.0.0.1
    - port       > 7545
    - network_id > *
Please check that your Ethereum client:
    - is running
    - is accepting RPC connections (i.e., "--rpc" option is used in geth)
    - is accessible over the network
    - is properly configured in your Truffle configuration file (truffle-config.js)

Here is my truffle-config.js file:

require('babel-register');
require('babel-polyfill');
require('dotenv').config();

module.exports = {
  networks: {
    development: {
      host: "127.0.0.1",
      port: 7545,
      network_id: "*" // Match any network id
    },
  },
  contracts_directory: './src/contracts/',
  contracts_build_directory: './src/abis/',
  compilers: {
    solc: {
      optimizer: {
        enabled: true,
        runs: 200
      }
    }
  }
}

I'm wondering if there's any way to check if the issue is the client can't accept RPC connections or if it's not accessible over the network as I don't think it's suggestions 1 and 4.

Answer 1

truffle migrate is used to deploy smart contracts to Ethereum networks (Ganache, public test nets and mainnet)!

In order to use truffle migrate you first need to have a smart contract in your ./Truffle/contracts folder

Then you say truffle compile to compile all the .sol files in the ./Truffle/contracts folder -> make sure to use a supported solidity version in your smart contract (you will get an error if yours isn't supported, just exchange your used version in the first line of your smart contract file with the required version)

Last but not least you need to go to ./Truffle/migrations folder to create 2_deploy_contract.js file containing following code:

const Migrations = artifacts.require("YOUR CONTRACT NAME");

module.exports = function (deployer) { deployer.deploy(Migrations); };

After all that you should be able to call truffle migrate and your smart contract gets deployed to your local Ethereum Ganache test net.

Answer 2

I solved my own problem by ensuring that the port number in my truffle-config.js agreed with the port number used by the running Ganache I shut down Ganache and then made the above correction in the truffle-config.js, and continued.

1. My initial relevant portion of truffle-config.js:
   • networks: { develop: { host: "127.0.0.1", port: 8545, network_id: '' } },
2. But my running Ganache process network port said: "RPC SERVER: HTTP://127.0.0.1:7545"
3. Then I changed the port number in truffle-config.js as follows:
   • networks: { develop: { host: "127.0.0.1", port: 7545, network_id: '' } },
4. Saved the truffle-config.js file, started Ganache, and ran the following command at the root directory of my project, in a separate terminal: truffle migrate --network develop
5. RESULT