我的系统：CentOS7 64位

环境需要：Go 1.9以上版本
geth工具

WARN [11-04|09:34:47.411] System clock seems off by -10h15m43.047110838s, which can prevent network connectivity 
WARN [11-04|09:34:47.411] Please enable network time synchronisation in system settings.

一.环境搭建

1.安装Go

下载源码 https://golang.org/dl/
找到适合自己操作系统的版本，必须1.9版本以上。我安装的是1.9.5
解压到/usr/local下

tar   -zxvf   go1.9.5.linux-amd64.tar.gz   -C /usr/local/

创建软链接

ln -s /usr/local/go/bin/bo  /usr/bin/go

测试是否成功

go version
#go version go1.9.5 linux/amd64

2.安装geth工具

下载geth源码

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

解压到/usr/local/下

unzip -d /usr/local/ go-ethereum-master.zip

编译源码

cd /usr/local/go-ethereum
make

成功的话会出现如下：

Done building.
Run "/usr/local/go-ethereum-master/build/bin/geth" to launch geth.

创建软链接这样我们可以直接用geth命令，而不用输入路径

ln -s /usr/local/go-ethereum-master/build/bin/geth /usr/bin/geth

二.搭建私有链

1.创建用户

mkdir geth
cd geth

进入geth控制台

geth  --datadir db  --nodiscover console

创建用户

> personal.newAccount()
Passphrase: 
Repeat passphrase: 
"0x12844bb3206f10a331557bffb7c8d34ee4ca8b65"
> personal.newAccount()
Passphrase: 
Repeat passphrase: 
"0xa6faa81cad6a3b038d9a51db80cedbe65184c7e2"

查看用户余额

> eth.getBalance(eth.accounts[0])
0
> eth.getBalance(eth.accounts[1])
0

给用户创建别名

> yujuan=eth.accounts[0]
"0x12844bb3206f10a331557bffb7c8d34ee4ca8b65"
> hcb=eth.accounts[1]
"0xa6faa81cad6a3b038d9a51db80cedbe65184c7e2"

可以看到在db目录下，有个keystore目录，里面已经存了我们刚刚创建的两个账户。

[root@localhost mychain]# tree
.
├── geth
│   ├── chaindata
│   │   ├── 000001.log
│   │   ├── CURRENT
│   │   ├── LOCK
│   │   ├── LOG
│   │   └── MANIFEST-000000
│   ├── LOCK
│   ├── nodekey
│   ├── nodes
│   │   ├── 000001.log
│   │   ├── CURRENT
│   │   ├── LOCK
│   │   ├── LOG
│   │   └── MANIFEST-000000
│   └── transactions.rlp
├── geth.ipc
└── keystore
    ├── UTC--2018-11-04T16-02-52.181405978Z--12844bb3206f10a331557bffb7c8d34ee4ca8b65
    └── UTC--2018-11-04T16-03-15.055116889Z--a6faa81cad6a3b038d9a51db80cedbe65184c7e2

2.传世区块配置文件

cd mychain
 vim gensis.json

在gensis.json中输入如下内容

{
   "alloc": {
      "0xc9228294cc6bc3e3fcdba0f5d393d68f920c7789": {
      "balance": "999000000000000000000"
      }
   },
    "config":{
        "chainId":15,
        "homesteadBlock":0,
        "eip155Block":0,
        "eip158Block":0
    },
    "nonce":"0x0000000000000001",
    "mixhash":"0x0000000000000000000000000000000000000000000000000000000000000000",
    "difficulty": "0x01",
    "coinbase":"0x0000000000000000000000000000000000000000",
    "timestamp": "0x00",
    "parentHash":"0x0000000000000000000000000000000000000000000000000000000000000000",
    "extraData": "0x777573686f756865",
    "gasLimit":"0xffffffff"
}

2.初始化

准备好创世区块配置文件后，需要初始化区块链，将上面的传世区块信息写入到区块链中。
新建一个目录用来存放区块链数据

mkdir db

进入geth目录，开始初始化区块

geth --datadir "./db" init gensis.json

–datadir 指定数据存放目录
成功的话可以看到如下结果

[root@localhost geth]#     geth --datadir "./db" init gensis.json
WARN [11-04|09:17:30.515] Sanitizing cache to Go's GC limits       provided=1024 updated=324
INFO [11-04|09:17:30.520] Maximum peer count                       ETH=25 LES=0 total=25
INFO [11-04|09:17:30.523] Allocated cache and file handles         database=/home/blockchain/geth/db/geth/chaindata cache=16 handles=16
INFO [11-04|09:17:30.548] Writing custom genesis block 
INFO [11-04|09:17:30.549] Persisted trie from memory database      nodes=1 size=149.00B time=111.297µs gcnodes=0 gcsize=0.00B gctime=0s livenodes=1 livesize=0.00B
INFO [11-04|09:17:30.550] Successfully wrote genesis state         database=chaindata                               hash=647de5…06c17e
INFO [11-04|09:17:30.550] Allocated cache and file handles         database=/home/blockchain/geth/db/geth/lightchaindata cache=16 handles=16
INFO [11-04|09:17:30.562] Writing custom genesis block 
INFO [11-04|09:17:30.563] Persisted trie from memory database      nodes=1 size=149.00B time=1.13319ms gcnodes=0 gcsize=0.00B gctime=0s livenodes=1 livesize=0.00B
INFO [11-04|09:17:30.563] Successfully wrote genesis state         database=lightchaindata                               hash=647de5…06c17e

并且在db目录中会生成geth和keystore两个文件夹，此时目录结构如下：

[root@localhost geth]# tree ./
./
├── db
│   ├── geth
│   │   ├── chaindata
│   │   │   ├── 000001.log
│   │   │   ├── CURRENT
│   │   │   ├── LOCK
│   │   │   ├── LOG
│   │   │   └── MANIFEST-000000
│   │   └── lightchaindata
│   │       ├── 000001.log
│   │       ├── CURRENT
│   │       ├── LOCK
│   │       ├── LOG
│   │       └── MANIFEST-000000
│   └── keystore
└── gensis.json

5 directories, 11 files

chaindata是存放区块数据，keystore是存放账户数据

以太坊搭建私有链(非常详细！！！）