This section explains everything about how to manage validator accounts using Prysm's built-in wallet, as well as setup instructions for different types of wallets including HD (hierarchical deterministic), non-HD, and remote signing wallets. If you created a wallet using the official eth2 launchpad and want to run Prysm using it, see our dedicated instructions here.
Prysm's validator accounts are extensible enough to allow for the most basic setup all the way to advanced production setups where security is paramount.
Out of the box, Prysm supports 3 basic kinds of wallets that encompass many different use-cases. In order of highest to lowest security:
- Remote signing wallet: (most secure) An advanced kind of wallet in which validator keys and signing requests are processed by a remote server via gRPC (view our remote server reference implementation).
- non-HD wallet: (good security) A simple wallet in which accounts are password protected and validator keys are generated non-deterministically. This is the recommended approach if you want to import an account from the eth2 launchpad and you can read dedicated instructions here.
- HD wallet: (least security) A common type of blockchain wallet which is generated from a english mnemonic, able to create new accounts deterministically. The encrypted seed is stored on day encrypted by a strong password. Given you are tying your HD wallet to the validator client, it is less secure than simply importing validating keys you need from an external source or running a remote signer.
At the core of Prysm's validator accounts lies the notion of a validator private key, which is stored in a password-protected, keystore.json file. Prysm supports the ability to manage many validator accounts, making it easy to import and export them as well as easily list all the account info in your wallet. Prysm is compliant with the EIP-2335 standards for storing eth2 validator private keys, making it possible to move keys between different eth2 client implementations.
Security for your keys is a big topic, but at its core, it is important to clarify the role of the private keys in eth2. When you generate a validator key, you actually generate 2 different ones: a withdrawal key and a validating key. The withdrawal key should be stored offline, and can be used to withdraw your gains in the future as it is not used during the validating process. Your validating key, however, needs to be accessible by your running validator client software at all times.
As a validator, you're expected to be consistently online to produce blocks and vote on others' blocks, as this is how you get rewarded for participating in eth2. To do this, your software needs to have instant access to your validating key, also referred to often as a "hot key" or access to a "hot wallet". Keeping your withdrawal key, or wallet mnemonic far away from your validator client is what will give you optimal security in eth2. If someone were to steal your validating keys, they wouldn't be able to withdraw your validator's staked ETH.
Keeping your wallet safe
When creating an HD wallet, you'll be given a 24-word mnemonic phrase which you need to store safely. Make sure you write it down somewhere safe offline, and do not leave traces of it on your computer. If someone gets ahold of this mnemonic, they can steal all your accounts!
The ideal security for an average user participating as a validator is as follows:
- Create a wallet using the official eth2.0-deposit-cli and keep your mnemonic stored offline, safely.
- Import only the validating keys you need into your validator client, such as by following the instructions here.
For best security in production cloud deployments, it's best you use a remote signer, as that offers absolute separation of your secret keys and your validator client software. Read more about remote signers here.
Non-HD wallets (Importing Keystores)
Prysm supports a non-deterministic wallet, which is a very simple kind of wallet storing validating keystores on disk, which can be imported from an external source such as the eth2.0-deposit-cli. This type of wallet makes it very easy to import and export accounts, useful for certain cloud deployments in which you don't want to store your eth2 withdrawal keys on-disk. This wallet is also the recommended approach if you generated a validator deposit using the eth2 launchpad.
By default, a Prysm validator client uses its own HD wallet, which you can recover from a 24-word, simple english sentence should you lose access to it, such as:
HD wallets are password protected via a high-entropy, strong password, and allow for easy creation of as many validator account as you wish.
Remote signing wallet
This is the most secure type of wallet. Some advanced users may wish to run a remote-signer server, which handles the retrieval of keys and signing of eth2 requests. A Prysm validator client can then connect securely via gRPC to the remote server and perform its validating duties by relying on the server for the information it needs. Most advanced cloud deployments should likely use this approach, as it is the most customizable.
To be compliant with a Prysm remote signing wallet, your remote signing server needs to implement the gRPC API specified in Prysm here.
We have also a created a reference remote signer implementation, maintained as an open source, Apache 2 project on Github here as a starting point.
Frequently asked questions
As you run your validator, you might run into unexpected errors or situations in which things aren't working as expected. Here are our answers to some of the most frequently asked questions.
How are my accounts stored? What data is stored on disk?
If you are running a simple import wallet (non-HD), we keep an encrypted file called
all-accounts.keystore.json protected by a strong password which contains your validating private keys and public keys. This file is stored in your wallet path.
If you are running an HD wallet, we store your encrypted wallet seed under your wallet path in a file named
encrypted.seed.json. This file is protected by a strong password you set during wallet creation, and we do not store your password.
If you are running a remote signer wallet, we do not store anything on disk except for the remote server credential information, such as the remote address and path to the TLS certificates required to establish a connection.
Why is my validator losing ETH despite my setup appearing ok?
If your validator client is running fine without errors but you're seeing your validator balance decrease, it is typically a sign your beacon node is either (a) crashed, (b) not synced to the chain head. This might also mean your beacon node doesn't have any peers and is likely not connected to anyone. To debug this problem, please read our guide on checking everything is running as expected. If this still does not resolve your issue, you can get in touch with our team on Discord anytime.
How can I use a hardware wallet with my validator?
At the moment, there is no built-in hardware wallet support for validators, but teams such as Ledger are working on integrating BLS12-381 keys (the type of keys used by eth2) into their products.
Help! Something is messed up with the validator and I can't start it
If you're encountering an unexpected issue that causes your client to crash or throw errors you cannot understand, you can always talk to your team on Discord.
How can I stop being a validator?
You can stop being a validator by issuing a voluntary exit, which is a special type of object included in the eth2 beacon chain that signifies your validator is ready to stop validating and securely exit the validator set. Although during phase 0 of eth2, you will not be able to withdraw your staking rewards, you can still issue a voluntary exit. You can find instructions for this process here.