Create and run a private ethereum network in Docker. This uses a development version of geth that is created locally so that we can test those changes in a private network environment.
To get started just clone the repo and got into the project root:
$ git clone https://github.com/cpurta/ethereum-docker-network
$ cd ethereum-docker-network
This project requires that you have a tagged geth docker image using the development
tag. This can be done by cloning https://github.com/ethereum/go-ethereum and then
running the following command:
$ docker build -t ethereum/client-go:development .
Once you have the development image tagged you can run your private network by
running the following command:
$ docker-compose up
This will by default make one bootstrap node, a ethereum node, and also run a netstats container so that you can monitor your network. From here you can monitor your network or deploy your own smart contracts to the network.
You can monitor your private network by using http://127.0.0.1:3000 and you will see
all the metrics about your network.
By default the docker-compose.yml will only start one node that is mining. If you
wish to scale more mining nodes you can do so by using the --scale flag when starting
the network.
Example:
N = number of nodes you want to run
$ docker-compose up --scale eth=N
What is the point of having a private network without being able to deploy you own smart contracts to it and test them out?
It is highly recommended that you have truffle installed to make deployment and
interacting with your contracts easier. If you do not have truffle you can install
it via npm install -g truffle.
You will need to have at least 3 terminal windows open to perform this and we will go through the following steps.
- Start the network
- Unlock the coinbase account on the bootstap node
- Use truffle to migrate and deploy a smart contract
You must have the private network running and instructions for getting that started
can be found above. Hint: In one terminal run: docker-compose up
In another terminal you must access the bootstrap node and this can be done by attaching to the bootstrap node container:
$ docker exec -it bootstrap_node geth attach /root/.ethereum/devchain/geth.ipc
You are now attached to the bootstrap node and using the geth javascript console. To unlock the account you can use the following command in the console:
> personal.unlockAccount(web3.eth.coinbase, "", 15000)
Now that the account is unlocked we can then go about deploying a contract to the network.
To deploy a smart contract to the private network it is recommended that the project
use truffle and has a network that points to localhost:8545. If you do not have such
a configuration more info can be found here.
In your third terminal you should be in a smart contracts repo that uses truffle and
has a network configured to use localhost:8545. You can then run:
$ truffle migrate --network private-network-rpc
If everything worked correctly your smart contract should have been deployed and you can use the truffle console to interact with your contract.
There are sometimes a few issues when deploying contracts that can be remedied:
- Deployments hanging on migration
- More than likely due to a DAG being built, so you will need to wait a few minutes sometimes
- Getting a
Error: authentication needed: password or unlockwhen deploying
- Either the coinbase account on the bootstrap node was never unlocked or you need to unlock again
Other Issue?
Feel free to make a DETAILED issue explaining what the expected behavior is and what occurred that was unexpected.
MIT