Importing from the Ethereum 2.0 Launch pad

The Eth2 Lauchpad is a website from the Ethereum Foundation which guides users how to use the eth2.0-deposit-cli command-line program to generate Eth2 validator keys.

The keys that are generated from eth2.0-deposit-cli can be easily loaded into a Lighthouse validator client (lighthouse vc). In fact, both of these programs are designed to work with each other.

This guide will show the user how to import their keys into Lighthouse so they can perform their duties as a validator. The guide assumes the user has already installed Lighthouse.


Whilst following the steps on the website, users are instructed to download the eth2.0-deposit-cli repository. This eth2-deposit-cli script will generate the validator BLS keys into a validator_keys directory. We assume that the user's present-working-directory is the eth2-deposit-cli repository (this is where you will be if you just ran the ./ script from the Eth2 Launch pad website). If this is not the case, simply change the --directory to point to the validator_keys directory.

Now, assuming that the user is in the eth2-deposit-cli directory and they're using the default (~/.lighthouse/{testnet}/validators) validators directory (specify a different one using --validators-dir flag), they can follow these steps:

1. Run the lighthouse account validator import command.

Docker users should use the command from the Docker section, all other users can use:

lighthouse --testnet medalla account validator import --directory validator_keys

Note: The user must specify the testnet that they are importing the keys for using the --testnet flag.

After which they will be prompted for a password for each keystore discovered:

Keystore found at "validator_keys/keystore-m_12381_3600_0_0_0-1595406747.json":

 - Public key: 0xa5e8702533f6d66422e042a0bf3471ab9b302ce115633fa6fdc5643f804b6b4f1c33baf95f125ec21969a3b1e0dd9e56
 - UUID: 8ea4cf99-8719-43c5-9eda-e97b8a4e074f

If you enter a password it will be stored in validator_definitions.yml so that it is not required each time the validator client starts.

Enter a password, or press enter to omit a password:

The user can choose whether or not they'd like to store the validator password in the validator_definitions.yml file. If the password is not stored here, the validator client (lighthouse vc) application will ask for the password each time it starts. This might be nice for some users from a security perspective (i.e., if it is a shared computer), however it means that if the validator client restarts, the user will be liable to off-line penalties until they can enter the password. If the user trusts the computer that is running the validator client and they are seeking maximum validator rewards, we recommend entering a password at this point.

Once the process is done the user will see:

Successfully imported keystore.
Successfully updated validator_definitions.yml.

Successfully imported 1 validators (0 skipped).


The import process is complete!

2. Run the lighthouse vc command.

Now the keys are imported the user can start performing their validator duties by running lighthouse vc and checking that their validator public key appears as a voting_pubkey in one of the following logs:

INFO Enabled validator       voting_pubkey: 0xa5e8702533f6d66422e042a0bf3471ab9b302ce115633fa6fdc5643f804b6b4f1c33baf95f125ec21969a3b1e0dd9e56

Once this log appears (and there are no errors) the lighthouse vc application will ensure that the validator starts performing its duties and being rewarded by the protocol. There is no more input required from the user.


The import command is a little more complex for Docker users, but the example in this document can be substituted with:

docker run -it \
	-v $HOME/.lighthouse:/root/.lighthouse \
	-v $(pwd)/validator_keys:/root/validator_keys \
	sigp/lighthouse \
	lighthouse --testnet medalla account validator import --directory /root/validator_keys

Here we use two -v volumes to attach:

  • ~/.lighthouse on the host to /root/.lighthouse in the Docker container.
  • The validator_keys directory in the present working directory of the host to the /root/validator_keys directory of the Docker container.