♦ License: Beerware Version 42++ This guide is continually updated on the wiki.Please see there to get the latest version: http://tech.lab.carl.pro/kb/ethereum/testnet_setup.Setting-up a local test Ethereum network is very useful for playing around, test free of Ether charge and develop – and it’s also very easy and fast.On this page, I have compiled one (of many) procedures describing how to do that.The aim was to explain a lot and make the procedure clear, so the page has become quite large.However, the entire process takes only 5 minutes and consists of around 5 Linux commands to execute (provided that Ethereum clients are installed and operational).The tutorial will be updated over time, new ideas added and improvements made.So be sure to check back from time to time :) To read more about the terminology encountered in the divers screens, have a look at my Technical Blockchain Encyclopaedia.Note: Ξ (Xi Uppercase) is the official currency symbol for Ether.I generally use ≢ to indicate Test-Ether or False-Ether, when this difference matters.

Prerequisite: UBUNTU, Mint or another UBUNTU based flavor ready for use.Ethereum client installed and operational.By default, the Ethereum client stores the Blockchain data and the account data in the “.ethereum” folder in the user’s home directory.When installing a test Blockchain, potentially in parallel to the official Blockchain, we have 2 easy options to direct Ethereum to use a different data directory than the one of the principal chain: 1) For each client command invocation, we specify the alternative data directory.2) We create a different user account that handles all things around the test Blockchain.The second solution is my favorite since it’s very easy to do on a Linux system and switching users adhoc is simple using the ‘su‘ command.The procedure described on this page uses the Linux user account ‘testnet1‘ as in charge for the alternative Blockchain.If you opt for using a different data directory instead, just specify the parameter “– -datadir ” in all Ethereum tool commands.

The Genesis block is the start block of the Blockchain – the first block, block 0, the only block that does not point to a predecessor block.It’s the entry point into the Blockchain database.The Genesis data defines initial parameters of the database and defines a cryptographically valid entry block.litecoin future 2017For more info, read here:The Blockchain Genesis Block.icp bitcoinIn order to set-up our private Ethereum Blockchain, we need to provide our own customised Genesis block.bitcoin est il une monnaieSince we don’t want to do heavy lifting to mine blocks, ie.bitcoin robinhoodallowing fast, single-threaded CPU mining, and we don’t want to be limited by Gas prices and limits, we set the various parameters accordingly.bitcoin mining setup youtube

The Genesis block does not define to which Blockchain a Miner connects to.Any Miner can mine on any Blockchain.A specific Blockchain is targeted by connecting to the corresponding peer-to-peer network.By default, geth uses a discovery protocol to find reachable peer Miners.When there are multiple Blockchains running on the same physical network, –networkid is used to specify which Miner group/network to connect to.how to post on bitcointalkIf not specified, “1” is used, which is the ID of the public Frontier network.bitcoin web oficialAlternatively, it is also possible to explicitly define peers using the –bootnodes, in combination with –nodiscover to prevent geth from looking for peers.bitcoin atm norwayNote that you have to work on the same Genesis block than the other peers in your group, otherwise all your mined Blocks will be rejected by the consensus rules.may dao bitcoin

The consequence of what has been said in the previous paragraph is that we can use the same Genesis block for multiple test networks.Note: The geeky values for nonce and mixhash in the above example are taken from the official Genesis extraction script, as distributed at the Frontier release.They satisfy the Block validity condition described in the specifications.Note: This procedure is just one of multiple variants.You could just start the geth with all parameters at the same time and let it run.Personally, I prefer a separation in order to divide everything in dedicated scripts later on.Lines with # are comment and are not to be typed.)When working with the local Blockchain, we need the run a Miner in order to have our transactions executed and included in the Blockchain.At the same time, we get some free test-ether that we can play with.Note that it makes no sense to keep the miner running when the test network is not used, and it makes no sense neither to use other resources than the CPU for mining.

With a Difficulty configured as low as in our custom Genesis block, the miner will find a valid block during each operation.When starting the miner for the first time, the DAG file is generated.The Blockchain becomes operational for testing as soon as the 5 first blocks are mined and confirmed.The commands below open various RPC/IPC interfaces to the network, which allows everyone able to connect to this machine to also control our miner and our wallet.It also allows execution from all domains (cf CORS).This is of course a security problem when done on a public network or/and using a real Ethereum wallet.If you wish to open more interfaces, just add the corresponding opcodes, as described in the documentation.Important to note as well is the command –networkid 1100.This “logically” isolates the local network Ethereum peer-to-peer network from others, especially the public Ethereum networks.Our network has the ID 1100 and all Nodes/Miners wanting to connect to our local network have to specify this ID.