Private network setup

Private_network.md

Ethereum private network setup

• Pre-requisites
• Setup

Getting Started

These instructions will allow you to get a ethereum private network up and running on your local machine for development and testing purposes.

• VM Specification

OS version :

Ubuntu 14.04.

RAM: 4GB

CPU: 2 cores

Pre-requisites

• How to install go-ethereum

sudo apt-get install software-properties-common
sudo add-apt-repository -y ppa:ethereum/ethereum
sudo apt-get update
sudo apt-get install ethereum

Check version

$ geth version

Other Operating systems: https://github.com/ethereum/go-ethereum/wiki/Building-Ethereum

Setup

Steps for setting up 2 peer network

1] Create new account on both peers

• Open new terminal

This step will create a new keystore file at location .../peer1/keystore/

Default directory = /root/.ethereum/keystore/

$ sudo mkdir peer1
$ geth --datadir="peer1" account new
Passphrase: xxxxxxxx
Repeat passphrase: xxxxxxxx
Address: {4e6cf0ed2d8bbf1fbbc9f2a100602ceba4bf1319}

Copy the displayed account address

• Open second terminal and follow above steps with folder name as peer2`.

2] Setup genesis.json

The genesis block is the start of the blockchain, and the genesis.json is the file that defines it.

sample here:

{
    "config": {
        "chainId": 56,
        "homesteadBlock": 0,
        "eip155Block": 0,
        "eip158Block": 0
    },

    "alloc": {
        "0x1517866f9935de27fea9da34e5a89c2de39855a2": {
            "balance": "1000000000000000000"
        }
    },

    "coinbase": "0x0000000000000000000000000000000000000000",
    "difficulty": "0x0400",
    "extraData": "",
    "gasLimit": "0x8000000",
    "nonce": "0x0000000000000042",
    "mixhash": "0x0000000000000000000000000000000000000000000000000000000000000000",
    "parentHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
    "timestamp": "0x00"
}

3] Add network details to genesis.json

• Add network id

chainid = networkId 

• Add Ethereum address of accounts created and balance in Wei (1 ethers=1000000000000000000 wei)

alloc:{
"[ Address here with 0x ]": { "balance": "1000000000000000000"}
}

4] Create genesis block in both peers:

This command initializes the genesis block for the network.

 $ sudo geth init "PathToGenesis.json"

5] Start first peer:

This command starts the ethereum client process --datadir -data directory that your private chain data will be stored in.  -- networkid flag - select network id. --port - network listening port. Default port is 30303 --rpc start rpc server.This is generally enabled by default in Geth. --rpcport select rpc port. Default port is 8545 --rpcaddr "0.0.0.0" '(Not Safe)' --rpccorsdomain specify URLs which can connect to your node in order to perform RPC client tasks '(Not Safe)' --nodiscover Dont connect to other peers automatically --unlock - keep account unlocked for the session. 0 - account [0]

$ sudo geth --datadir="peer1" --networkid 56 --port 30303 --rpc --rpcport 8545 --rpcaddr "0.0.0.0"  --rpccorsdomain "*"  --nodiscover --unlock 0 console  

6] Start Second peer at different port :

Start second peer as Miner -- etherbase flag - set miner account. --mine - Start mining

$ sudo geth --datadir="peer2"  --networkid 56 --port 30304 --rpc  --rpcport 8546 --rpcaddr "0.0.0.0" --rpccorsdomain "*" --etherbase "0x0000000000000000000000000000000000000000" --mine --nodiscover --unlock 0 console

stop mining:

miner.stop()
miner.start()

7] Connect peers

• get enode id

admin.nodeInfo.enode
"enode://704899633efe7dc6178dad6e66c318bebb8633bc8fe141b2f53e7104b5feee3f0c5eb153e634d9939e73b75c268d36a16bd5f7b15d91090452f60508455cc61d@[::]:30303"

• add peer with enode id

 admin.addPeer("enode://704899633efe7dc6178dad6e66c318bebb8633bc8fe141b2f53e7104b5feee3f0c5eb153e634d9939e73b75c268d36a16bd5f7b15d91090452f60508455cc61d
@33.4.2.1:30303")

format: "enode://pubkey@ip:port"

Geth supports a feature called static nodes if you have certain peers you always want to connect to. Static nodes are re-connected on disconnects. You can configure permanent static nodes by putting something like the following into datadir/static-nodes.json (this should be the same folder that the chaindata and keystore folders are in)

[
  "enode://f4642fa65af50cfdea8fa7414a5def7bb7991478b768e296f5e4a54e8b995de102e0ceae2e826f293c481b5325f89be6d207b003382e18a8ecba66fbaf6416c0@33.4.2.1:30303",
  "enode://pubkey@ip:port"
]

• Check peer connection

admin.peers
[{
  ID: 'a4de274d3a159e10c2c9a68c326511236381b84c9ec52e72ad732eb0b2b1a2277938f78593cdbe734e6002bf23114d434a085d260514ab336d4acdc312db671b',
  Name: 'Geth/v0.9.14/linux/go1.4.2',
  Caps: 'eth/60',
  RemoteAddress: '5.9.150.40:30301',
  LocalAddress: '192.168.0.28:39219'
}]

Additional Steps

new connection to the geth process

$ geth attach ipc:./geth.ipc

Check balance in account

primary = eth.accounts[0];
web3.fromWei(eth.getBalance(primary), "ether");

private network: https://github.com/ethereum/go-ethereum

Contract Deployment

Compile Deploy contracts using browser browser-solidity: http://ethereum.github.io/browser-solidity/