lighthouse/scripts/local_testnet

Simple Local Testnet

These scripts allow for running a small local testnet with multiple beacon nodes and validator clients and a geth execution client. This setup can be useful for testing and development.

Requirements

The scripts require lcli, lighthouse, geth, bootnode to be installed on PATH.

MacOS users need to install GNU sed and GNU grep, and add them both to PATH as well.

From the root of this repository, run:

make
make install-lcli

Starting the testnet

Modify vars.env as desired.

The testnet starts with a post-merge genesis state. Start a consensus layer and execution layer boot node along with BN_COUNT number of beacon nodes each connected to a geth execution client and VC_COUNT validator clients.

The start_local_testnet.sh script takes four options -v VC_COUNT, -d DEBUG_LEVEL, -p to enable builder proposals and -h for help. It also takes a mandatory GENESIS_FILE for initialising geth's state. A sample genesis.json is provided in this directory.

The ETH1_BLOCK_HASH environment variable is set to the block_hash of the genesis execution layer block which depends on the contents of genesis.json. Users of these scripts need to ensure that the ETH1_BLOCK_HASH variable is updated if genesis file is modified.

The options may be in any order or absent in which case they take the default value specified.

• VC_COUNT: the number of validator clients to create, default: BN_COUNT
• DEBUG_LEVEL: one of { error, warn, info, debug, trace }, default: info

./start_local_testnet.sh genesis.json

Stopping the testnet

This is not necessary before start_local_testnet.sh as it invokes stop_local_testnet.sh automatically.

./stop_local_testnet.sh

Manual creation of local testnet

These scripts are used by ./start_local_testnet.sh and may be used to manually

Assuming you are happy with the configuration in vars.env, create the testnet directory, genesis state with embedded validators and validator keys with:

./setup.sh

Note: The generated genesis validators are embedded into the genesis state as genesis validators and hence do not require manual deposits to activate.

Generate bootnode enr and start an EL and CL bootnode so that multiple nodes can find each other

./bootnode.sh
./el_bootnode.sh

Start a geth node:

./geth.sh <DATADIR> <NETWORK-PORT> <HTTP-PORT> <AUTH-HTTP-PORT> <GENESIS_FILE>

e.g.

./geth.sh $HOME/.lighthouse/local-testnet/geth_1 5000 6000 7000 genesis.json

Start a beacon node:

./beacon_node.sh <DATADIR> <NETWORK-PORT> <HTTP-PORT> <EXECUTION-ENDPOINT> <EXECUTION-JWT-PATH> <OPTIONAL-DEBUG-LEVEL>

e.g.

./beacon_node.sh $HOME/.lighthouse/local-testnet/node_1 9000 8000 http://localhost:6000 ~/.lighthouse/local-testnet/geth_1/geth/jwtsecret

In a new terminal, start the validator client which will attach to the first beacon node:

./validator_client.sh <DATADIR> <BEACON-NODE-HTTP> <OPTIONAL-DEBUG-LEVEL>

e.g. to attach to the above created beacon node

./validator_client.sh $HOME/.lighthouse/local-testnet/node_1 http://localhost:8000

You can create additional beacon node and validator client instances with appropriate parameters.

Additional Info

Adjusting number and distribution of validators

The VALIDATOR_COUNT parameter is used to specify the number of insecure validator keystores to generate and make deposits for. The BN_COUNT parameter is used to adjust the division of these generated keys among separate validator client instances. For e.g. for VALIDATOR_COUNT=80 and BN_COUNT=4, the validator keys are distributed over 4 datadirs with 20 keystores per datadir. The datadirs are located in $DATADIR/node_{i} which can be passed to separate validator client instances using the --datadir parameter.

Starting fresh

Delete the current testnet and all related files using. Generally not necessary as start_local_test.sh does this each time it starts.

./clean.sh

Updating the genesis time of the beacon state

If it's been a while since you ran ./setup then the genesis time of the genesis state will be far in the future, causing lots of skip slots.

Update the genesis time to now using:

./reset_genesis_time.sh

Note: you probably want to just rerun ./start_local_testnet.sh to start over but this is another option.