上篇部落格介紹了在一臺電腦上配置多個geth節點，同時再最後也有個問題，多臺電腦之間連線沒有成功，後來多方研究之後，搭建成功了。防火牆沒關！！！
Ubuntu系統關閉防火牆命令：sudo ufw disable

現在三臺電腦：電腦一 219.216.65.127（Ubuntu）、電腦二 219.216.65.139（Windows）、電腦三 219.216.64.144（Ubuntu）

三臺電腦上的genesis.json檔案要相同，建立一樣的創世區塊；然後networkid要相同，屬於同一個網路。genesis.json檔案如下：

{
  "nonce": "0x0000000000000042",
  "timestamp
 
": "0x00",
  "parentHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
  "extraData": "0x00",
  "gasLimit": "0x80000000",
  "difficulty": "0x01",
  "mixhash": "0x0000000000000000000000000000000000000000000000000000000000000000",
  "coinbase": "0x3333333333333333333333333333333333333333",
  "alloc": {     }
}

好了，現在來在三臺電腦上各自建立一個節點

電腦一

//建立創世區塊
$ geth --datadir ~/ether/n1 init genesis.json

# 啟動console
$ geth --identity "hello"
 
 --datadir ~/ether/n1 --port 30301 --rpcport 8101 --networkid 12345 console 2>> ~/ether/n1/geth.log

啟動成功，獲取節點資訊，方便後面連線。

> admin.nodeInfo
{
  enode: "enode://2c196b02b23598426f3915dbd7a1e8e178b067b3e9921af6849e42027ec41f73f[email protected][::]:30301",
  id: "2c196b02b23598426f3915dbd7a1e8e178b067b3e9921af6849e42027ec41f73f6febc27b52da7e77c0edf69412b0231b886904c750167de335ead2798de12ff"
 
,
  ip: "::",
  listenAddr: "[::]:30301",
  name: "Geth/v1.4.5-stable-a269a713/linux/go1.4.2/hello",
  ports: {
    discovery: 30301,
    listener: 30301
  },
  protocols: {
    eth: {
      difficulty: 5290384,
      genesis: "0x6099b65e564bd511f49e8f39ba27b6a68b6b78fd1481592257f06bbf93abe624",
      head: "0x337f2059a1a6d82aee1afba91828d86a8a3b6f85d83b8cb2f8a9210af3b29c1c",
      network: 12345
    }
  }
}

同樣地，在電腦二、三上建立創世區塊，啟動console，獲取它們的節點資訊，然後在電腦一上連線另外兩臺電腦上的節點。

電腦二的enode:

"enode://54b7b1dccbe37148cda6e0c9889d23ffb8e2efc905f3c2d001cd66b3b513210a4[email protected][::]:30301"

電腦三的enode:

"enode://07954219f1a52acfa7562ac841e77860505bb6f6cc948bc540b94326606679d33[email protected][::]:30301"

電腦一連線電腦二和電腦三：

>admin.addPeer("enode://54b7b1dccbe37148cda6e0c9889d23ffb8e2efc905f3c2d001cd66b3b513210a4a426706bab795d83d0c236b9b1647f46947d86c48ac8faf7f802aff318c4aa1@219.216.65.139:30301")

>admin.addPeer("enode://07954219f1a52acfa7562ac841e77860505bb6f6cc948bc540b94326606679d33e805a21b21cb105eaf58f449b0acc84893560919afee00bbc01b8a3fc0213af@219.216.64.144:30301")

現在可以看見連線的數量：

> net.peerCount
2
> admin.peers
[{
    caps: ["eth/61", "eth/62", "eth/63"],
    id: "07954219f1a52acfa7562ac841e77860505bb6f6cc948bc540b94326606679d33e805a21b21cb105eaf58f449b0acc84893560919afee00bbc01b8a3fc0213af",
    name: "Geth/v1.4.5-stable-a269a713/linux/go1.6.2/hello",
    network: {
      localAddress: "219.216.65.127:30301",
      remoteAddress: "219.216.64.144:36332"
    },
    protocols: {
      eth: {
        difficulty: 5290384,
        head: "337f2059a1a6d82aee1afba91828d86a8a3b6f85d83b8cb2f8a9210af3b29c1c",
        version: 63
      }
    }
}, {
    caps: ["eth/61", "eth/62", "eth/63"],
    id: "54b7b1dccbe37148cda6e0c9889d23ffb8e2efc905f3c2d001cd66b3b513210a4a426706bab795d83d0c236b9b1647f46947d86c48ac8faf7f802aff318c4aa1",
    name: "Geth/v1.4.5-stable/windows/go1.6.2/hello",
    network: {
      localAddress: "219.216.65.127:30301",
      remoteAddress: "219.216.65.139:50911"
    },
    protocols: {
      eth: {
        difficulty: 5290384,
        head: "337f2059a1a6d82aee1afba91828d86a8a3b6f85d83b8cb2f8a9210af3b29c1c",
        version: 63
      }
    }
}]

現在可以看見兩個節點都連線成功。主要是防火牆的問題！