Setting up a private Ethereum blockchain with two nodes

8/19/2019 Setting up a private Ethereum blockchain with two nodes

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1 - Setting up a private Ethereum blockchain with two nodes (or more) and VmWare

Setting up a private Ethereum blockchain with twonodes (or more) and VmWare

[FOR TESTING PURPOSES ONLY]

By Eng. Hectór Ugarte 24.03.2016

1. Prerequisites

VmWare Workstation (mine: VMware Workstation 12 Pro). Ubuntu iso (mine: Ubuntu 15.10)2. Procedure.A. Create two virtual machines on VmWare, running Ubuntu. Recommended specifications:

B. Set both virtual machines on the same network, for example:

C. Install Geth on both nodes:sudo apt-get install software-properties-commonsudo add-apt-repository -y ppa:ethereum/ethereumsudo apt-get updatesudo apt-get install ethereum




D. Create a new folder on both virtual machines, called it “Ethereum ”, and inside that folderanother one, called it “datadir ”

E. Create a new file inside Ethereum folder, called it “genesis.json ” with the next content:

{"nonce": "0xdeadbeefdeadbeef","timestamp": "0x0","parentHash":

"0x0000000000000000000000000000000000000000000000000000000000000000","extraData": "0x0","gasLimit": "0x8000000","difficulty": "0x400","mixhash":

"0x0000000000000000000000000000000000000000000000000000000000000000","coinbase": "0x3333333333333333333333333333333333333333","alloc": {

}}

F. Now start the geth client on both nodes.

geth --genesis --datadir --networkid 12344321 --nodiscover --maxpeers 1console

Where:

1. Use genesis.json as the genesis block.

2. Use datadir folder to put your all the necessary data about the private

3. Use a network id other than ‘1’ to ensure we can’t talk to nodes from the main network – “connections between nodes are valid only if peers have identical protocol version and network id”

4. Disable peer discovery

5. Set a maximum of 1 peers (or more if you want to use more peers)

6. Starts geth in console mode so you can interact with your new blockchain / node

For example:

sudo geth --genesis="/home/hedugaro/Ethereum/genesis.json" --datadir="/home/hedugaro/Ethereum/datadir" --networkid 12344321 --nodiscover --maxpeers 1 console

G. Create Accounts

Once geth is up and you get a console, create your own account with the following command:




>personal.newAccount("mypass");

Where “mypass ” is your desired password. You get as answer for example:

'0xd47eaceb073dc03e3330b4747b1224f146f8d6e7'

Repeat this on the other nodes.H. Connect the 2 Nodes as Peers

First, find the enode of the first node with the next command:

admin.nodeInfo.enode

You get as answer:

"enode://4e0312fb3eae8b59048afb1a53a3cd4a157db1fb2c8b7175176ffa932e41c22c60dd5f7540bbfb7d25b4c443116895360064fe4415734d3da621b29b0a7b6b6e@ [::]:30303?discport=0"

Instead of [::] , add your ip address to that string, for example: (you can get your ip address withifconfig command)

"enode://4e0312fb3eae8b59048afb1a53a3cd4a157db1fb2c8b7175176ffa932e41c22c60dd5f7540bbfb7d25b4c443116895360064fe4415734d3da621b29b0a7b6b6e@172.16.1.104:30303?discport=0"

On the second node, add node one as a peer with the following command:

>admin.addPeer("enode://4e0312fb3eae8b59048afb1a53a3cd4a157db1fb2c8b7175176ffa932e41c22c60dd5f7540bbfb7d25b4c443116895360064fe4415734d3da621b2

[email protected]:30303?discport=0")I. Check if everything went ok, with the command:

web3.net.peerCount

You should get as response 1

Now the two nodes are configured on a private blockchain.

At least one node should be mining.

J. To do that:

miner.setEtherbase(eth.accounts[0])

and

miner.start()

K. It will take around 10 minutes to produce the DAG file (needed for mining) (Dagger-Hashimoto)




L. After the DAG is produced, the mining procedure will start. You can check that the minneraccount balance is increasing, calling the function getbalance, for example:

web3.eth.getBalance("0xc6acbafc19fbcb5ee3af6bf471c0c510e3d9d0c2")

Useful information:

Website: https://www.ethereum.org/

Blog: http://blog.ethereum.org/

Homestead documentation: http://www.ethdocs.org/

Reedit: http://www.reddit.com/r/ethereum

Forum: https://forum.ethereum.org/

https://www.ethereum.org/



http://blog.ethereum.org/



http://www.ethdocs.org/



http://www.reddit.com/r/ethereum



https://forum.ethereum.org/








Setting up a private Ethereum blockchain with two nodes

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