Ethermint

Overview

Ethermint enables ethereum to run as an ABCI application on tendermint and the COSMOS hub. This application allows you to get all the benefits of ethereum without having to run your own miners.

This means running an Ethereum EVM-based network that uses Tendermint consesnsus instead of proof-of-work. The way it's built makes it easy to use existing Ethereum tools (geth attach, web3) to interact with the node.

Install

Currently, we are not shipping executable binaries and hence you have to build ethermint from source. To do so, please install go1.8. Once you have go installed you can build the ethermint executable by running git clone https://github.com/tendermint/ethermint.git. Afterwards, please switch into the ethermint directory and run make install, which will place the binary in your $GOPATH.

You will also need to have tendermint installed. Please follow this guide.

Getting started

To get started, you need to initialise the genesis block for tendermint core and go-ethereum. This is still a work in progress, but it's possible to do:

You can choose where to store the ethermint files with --datadir. For this guide, we will use ~/.ethermint, which is a reasonable default in most cases.

Tendermint

First you need to initialise the tendermint engine

tendermint init --home ~/.ethermint/tendermint

and then run it with

tendermint node --home ~/.ethermint/tendermint

Ethermint

First you need to initialise ethermint. For that please switch into the source code folder for ethermint.

ethermint --datadir ~/.ethermint init dev/genesis.json
cp -r dev/keystore ~/.ethermint/keystore

And the you can run ethermint with

ethermint --datadir ~/.ethermint --rpc --rpcaddr=0.0.0.0 --ws --wsaddr=0.0.0.0 --rpcapi eth,net,web3,personal,admin

The dev/genesis.json file specifies some initial ethereum account with funds, and the corresponding private key is copied over from dev/keystore. The password to this key is 1234

Geth

Lastly, you can use all the cool ethereum tools that you are already used to. For example, you can use geth to interact with the ethereum instance.

geth attach http://localhost:8545

or

geth attach ~/.ethermint/geth.ipc

will drop you into a web3 console.

instance: Geth/linux/go1.7.4
coinbase: 0x7eff122b94897ea5b0e2a9abf47b86337fafebdc
at block: 71 (Thu, 16 Feb 2017 16:08:20 EST)
 datadir: /home/user/.ethermint
 modules: admin:1.0 debug:1.0 eth:1.0 personal:1.0 rpc:1.0 txpool:1.0 web3:1.0

> primary = eth.accounts[0]
"0x7eff122b94897ea5b0e2a9abf47b86337fafebdc"
> balance = web3.fromWei(eth.getBalance(primary), "ether");
10000000000000000
> personal.unlockAccount(primary, "1234", 100)
true
>

And you're off!

Mining reward and validator management

Ethermint implements hooks that can be customized for mining rewards and validator management. The default at this point is to not reward and not change the validator set. Example strategies can be found in the strategies folder.