How to set up and use Proof of Stake (PoS)
Last updated
Last updated
This guide goes into detail on how to set up a Proof of Stake network with the alveychain, how to stake funds for nodes to become validators and how to unstake funds.
It highly encouraged to read and go through the / sections, before going along with this PoS guide. These sections outline the steps needed to start a Proof of Authority (PoA) cluster with the alveychain.
:::warning PoA and PoS chains incompatible A chain that has previously been running in PoA mode, cannot be converted to a PoS chain during execution, and vice versa.
The only way to switch consensus mechanisms is to reset the chain and start it in the corresponding mode (PoA or PoS) from scratch. :::
Currently, there is no limit to the number of validators that can stake funds on the Staking Smart Contract.
The repo for the Staking Smart Contract is located .
It holds the necessary testing scripts, ABI files and most importantly the Staking Smart Contract itself.
Setting up a cluster with the alveychain is covered in the / sections.
The only difference between setting up a PoS and PoA cluster is in the genesis generation part.
When generating the genesis file for a PoS cluster, an additional flag is needed --pos:
To set the size of an epoch for a cluster (in blocks), when generating the genesis file, an additional flag is specified --epoch-size:
This value specified in the genesis file that the epoch size should be 50 blocks.
The default value for the size of an epoch (in blocks) is 100000.
The default epoch length in blocks (100000) may be a long time to way for validator set updates. Considering that new blocks are added ~2s, it would take ~55.5h for the validator set to possibly change.
Setting a lower value for the epoch length ensures that the validator set is updated more frequently. :::
The Staking Smart Contract repo is a Hardhat project, which requires NPM.
To initialize it correctly, in the main directory run:
Create an .env file with the following parameters in the Smart Contracts repo location:
Where the parameters are:
JSONRPC_URL - the JSON-RPC endpoint for the running node
PRIVATE_KEYS - private keys of the staker address
STAKING_CONTRACT_ADDRESS - the address of the staking smart contract ( default 0x0000000000000000000000000000000000001001)
:::info Staking address The Staking Smart Contract is pre-deployed at address 0x0000000000000000000000000000000000001001.
Any kind of interaction with the staking mechanism is done through the Staking Smart Contract at the specified address.
In order to become part of the validator set, an address needs to stake a certain amount of funds above a threshold.
Currently, the threshold for becoming part of the validator set is 1 ETH.
Staking can be initiated by calling the stake method of the Staking Smart Contract, and specifying a value >= 1 ETH.
The stake Hardhat script stakes a default amount of 1 ETH, which can be changed by modifying the scripts/stake.ts file.
If the funds being staked are >= 1 ETH, the validator set on the Staking Smart Contract is updated, and the address will be part of the validator set starting from the next epoch.
Addresses that have a stake can only unstake all of their funds at once.
All addresses that stake funds are saved to the Staking Smart Contract.
Epochs are covered in detail in the section.
:::info Lowering the epoch length As outlined in the section, epoch blocks are used to update the validator sets for nodes.
Scripts for interacting with the deployed Staking Smart Contract are located on the .
To learn more about the Staking Smart Contract, please visit the section. :::
After the .env file mentioned in the has been set up, and a chain has been started in PoS mode, staking can be done with the following command in the Staking Smart Contract repo:
After the .env file mentioned in the has been set up, and a chain has been started in PoS mode, unstaking can be done with the following command in the Staking Smart Contract repo:
After the .env file mentioned in the has been set up, and a chain has been started in PoS mode, fetching the list of validators can be done with the following command in the Staking Smart Contract repo: