Web3Signer is a tool by Consensys which allows remote signing. Remote signing is when a Validator Client (VC) out-sources the signing of messages to remote server (e.g., via HTTPS). This means that the VC does not hold the validator private keys.
Using a remote signer comes with risks, please read the following two warnings before proceeding:
Remote signing is generally only desirable for enterprise users or users with unique security requirements. Most users will find the separation between the Beacon Node (BN) and VC to be sufficient without introducing a remote signer.
Using a remote signer introduces a new set of security and slashing risks and should only be undertaken by advanced users who fully understand the risks.
The Web3Signer tool is maintained by Consensys, the same team that maintains Teku. The Lighthouse team (Sigma Prime) does not maintain Web3Signer or make any guarantees about its safety or effectiveness.
A remote signing validator is added to Lighthouse in much the same way as one that uses a local
keystore, via the
validator_definitions.yml file or via the
POST /lighthouse/validators/web3signer API endpoint.
Here is an example of a
validator_definitions.yml file containing one validator which uses a
--- - enabled: true voting_public_key: "0xa5566f9ec3c6e1fdf362634ebec9ef7aceb0e460e5079714808388e5d48f4ae1e12897fed1bea951c17fa389d511e477" type: web3signer url: "https://my-remote-signer.com:1234" root_certificate_path: /home/paul/my-certificates/my-remote-signer.pem
When using this file, the Lighthouse VC will perform duties for the
0xa5566.. validator and defer
https://my-remote-signer.com:1234 server to obtain any signatures. It will load a
"self-signed" SSL certificate from
/home/paul/my-certificates/my-remote-signer.pem (on the
filesystem of the VC) to encrypt the communications between the VC and Web3Signer.
request_timeout_mskey can also be specified. Use this key to override the default timeout with a new timeout in milliseconds. This is the timeout before requests to Web3Signer are considered to be failures. Setting a value that it too-long may create contention and late duties in the VC. Setting it too short will result in failed signatures and therefore missed duties.