私有Ethereum 搭建

首先，将go-ethereum从github上clone下来

git  clone https://github.com/ethereum/go-ethereum.git

然后，安装最新版本的GO语言包
因为geth需要使用GO和C的编译器，所以执行以下代码：

sudo apt-get install -y build-essential

最后，进入go-ethereum文件夹，并编译go-ethereum：

cd go-ethereum
make geth

编译好之后，可以在build/bin/geth中执行geth
创建private-ethereum文件夹用来保存key和数据，并进入private-ethereum文件夹

mkdir private-ethereum
cd private-ethereum

在执行geth之前，首先创建账户

geth --datadir ./data account new

并记住产生的账户地址
随后在private-ethereum中创建genesis.json文件

{
    "config" : {
    "chainId": 10,
    "homesteadBlock": 0,
  "eip150Block": 0,
  "eip150Hash": "0x0000000000000000000000000000000000000000000000000000000000000000",
  "eip155Block": 0,
  "eip158Block": 0,
  "byzantiumBlock": 0,
  "constantinopleBlock": 0,
  "petersburgBlock": 0,
  "ethash": {}
    },
    "difficulty" : "0x10",
    "extraData"  : "0x00",
    "gasLimit"   : "0xffffffffff",
    "nonce"      : "0xdeadbeefdeadbeef",
    "mixhash"    : "0x0000000000000000000000000000000000000000000000000000000000000000",
    "parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
    "timestamp"  : "0x00",
    "alloc"      : {
        "0x004E00477eC7729D5FE105e27BAeFbBeAa4a4f12": { "balance": "9999999999999" },
        "0x806EFBbefD03Fb4817Cc049997a57A683FEcfa28": { "balance": "9999999999999" }
    }
}

注意，alloc里面的地址即为刚刚创建好的账户地址，并且为他们分配了一定量的balance
有了genesis.json文件，我们就可以初始化区块链数据：

geth --nousb --datadir ./data init genesis.json

随后便可以启动geth：

geth --allow-insecure-unlock --nousb --identity "newEth" --rpc --rpcport 8545 --rpcaddr 0.0.0.0 --rpccorsdomain "*" --datadir "data" --port 30303 --rpcapi "eth,net,web3" --networkid 999 console

注意，这里面--allow-insecure-unlock可以在console中解锁账户。

如果需要使用POA挖矿方式，使用一下genesis.json

{
    "config" : {
    "chainId": 10,
    "homesteadBlock": 0,
  "eip150Block": 0,
  "eip150Hash": "0x0000000000000000000000000000000000000000000000000000000000000000",
  "eip155Block": 0,
  "eip158Block": 0,
  "byzantiumBlock": 0,
  "constantinopleBlock":0,
  "petersburgBlock": 0,
  "clique": {
    "period": 1,
    "epoch": 300
}
    },
    "difficulty" : "0x00",
    "extraData"  : "0x0000000000000000000000000000000000000000000000000000000000000000004e00477ec7729d5fe105e27baefbbeaa4a4f120000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
    "gasLimit"   : "0xffffffffffff",
    "nonce"      : "0xdeadbeefdeadbeef",
    "mixhash"    : "0x0000000000000000000000000000000000000000000000000000000000000000",
    "parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
    "timestamp"  : "0x00",
    "alloc"      : {
        "0x004E00477eC7729D5FE105e27BAeFbBeAa4a4f12": { "balance": "0xffffffffffff" },
        "0x806EFBbefD03Fb4817Cc049997a57A683FEcfa28": { "balance": "0xffffffffffff" }
    }
}

注意，extraData中间为signer的地址。