區塊鏈入門(2):搭建以太坊私有鏈,執行挖礦.

在做一些測試工作的時候, 為了方便控制以及更快的進入真正的測試工作,可能需要搭建一個私有的以太坊網絡.

而以太坊節點之間能夠互相鏈接需要滿足1)相同的協議版本2)相同的networkid,所以搭建私有網絡最方便的方法就是通過geth命令中的--networkid選項,設置一個與主網不同的networkid(主網的networkid為1),這也是官方推薦的方法.

下面開始建立私有以太坊網絡:

mkdir private-geth
cd private-geth

建立創世紀區塊文件,是一個json格式的文件:

vim genesis.json

在創世紀區塊的json文件中填入以下內容, 並保存.

{
    "config": {
        "chainId": 15,
        "homesteadBlock": 0,
        "eip155Block": 0,
        "eip158Block": 0
    },
    "coinbase" : "0x0000000000000000000000000000000000000000",
    "difficulty" : "0x40000",
    "extraData" : "",
    "gasLimit" : "0xffffffff",
    "nonce" : "0x0000000000000042",
    "mixhash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
    "parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
    "timestamp" : "0x00",
    "alloc": { }
}

初始化創世紀節點,並設置data目錄:

geth --datadir ./data/00 init genesis.json

啟動節點, 加上console 表示啟動后,啟用命令行:

geth --datadir ./data/00 --networkid 15 console

 

 

現在私有網絡就搭建成功,下面就可以在這個剛剛搭建出來的私有以太坊網絡中執行挖礦操作了,

挖礦首先必須有一個賬戶,輸入下面的命令,查看當前node中的所有賬戶:

 

> eth.accounts
[]
###輸出了一個"[]",說明毛都么有一根,更別說賬戶了.既然沒有,那就來創建一個,繼續輸入命令:
> personal.newAccount("123456")
###正常情況,命令行會輸出:
INFO [05-15|23:59:29] New wallet appeared                      url=keystore:///home/zl/Documents/p… status=Locked
"0x5b901c2495c077f515ae84fc53206f2eb3bf8296"
###再用之前查看賬戶的命令看看:
> eth.accounts
["0x5b901c2495c077f515ae84fc53206f2eb3bf8296"]
###有輸出了"0x5b.......96"這一串就是賬戶的地址.
###賬戶有了,接下來做點更有意思的事,開始挖礦....繼續在命令行書輸出:
> miner.start()
INFO [05-16|00:07:25] Updated mining threads                   threads=0
INFO [05-16|00:07:25] Starting mining operation 
null
INFO [05-16|00:07:25] Commit new mining work                   number=1 txs=0 uncles=0 elapsed=38.053ms
INFO [05-16|00:07:28] Generating DAG in progress               epoch=0 percentage=0 elapsed=1.715
INFO [05-16|00:07:30] Generating DAG in progress               epoch=0 percentage=1 elapsed=3.448s
INFO [05-16|00:07:31] Generating DAG in progress               epoch=0 percentage=2 elapsed=5.059s
INFO [05-16|00:07:33] Generating DAG in progress               epoch=0 percentage=3 elapsed=6.799s
INFO [05-16|00:07:35] Generating DAG in progress               epoch=0 percentage=4 elapsed=8.373s
...................................這個percenage=100,也就是100%以后.,就不斷的出現下面的提示.............
INFO [05-16|00:24:54] Successfully sealed new block            number=36 hash=95fdfd…1411ee
INFO [05-16|00:24:54] 🔗 block reached canonical chain          number=31 hash=438022…f6592e
.................................好多這個提示,挖到好多礦................................
INFO [05-16|00:24:54] 🔨 mined potential block                  number=36 hash=95fdfd…1411ee
INFO [05-16|00:24:54] Commit new mining work                   number=37 txs=0 uncles=0 elapsed=122.202µs
###然后停止挖礦:
>miner.stop(
true
###然后再來看看我們賬戶錢包有多少礦了:
> eth.getBalance(eth.accounts[0])
355000000000000000000

下一篇,我會講一講如何搭建 私有網絡節點群:

Setting up private network or local cluster

參考文檔:

http://ethdocs.org/en/latest/network/test-networks.html?highlight=private%20chain

https://github.com/ethereum/go-ethereum/wiki/Private-network

https://github.com/ethereum/go-ethereum/wiki/Setting-up-private-network-or-local-cluster

http://chainskills.com/2017/03/10/part-3-setup-the-private-chain-miners/