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How to spawn a new child chain

In this section, we'll prepare initiate a new chain with PolyBFT consensus and prepare the initial Furtheon nodes.

1. Generate Keys

To initialize PolyBFT consensus, we need to generate the necessary secrets for each node.

The polygon-edge polybft-secrets command is used to generate account secrets for validators. The command initializes private keys for the consensus client (validators + networking) to a Secrets Manager config file.

Flags ↓ | Flag | Description | Example | |-----------------|-----------------------------------------------------------------------------------------------------------|----------------------------| | `--account` | The flag indicating whether a new account is created (default true). | | | `--config` | The path to the SecretsManager config file. If omitted, the local FS secrets manager is used. | `--config /path/to/config` | | `--data-dir` | The directory for the Furtheon data if the local FS is used. | `--data-dir /path/to/dir` | | `--insecure` | The flag indicating whether the secrets stored on the local storage should be encrypted. | | | `--network` | The flag indicating whether a new Network key is created (default true). | | | `--num` | The flag indicating how many secrets should be created, only for the local FS (default 1). | `--num 4` | | `--output` | The flag indicating to output existing secrets. | `--output` | | `--private` | The flag indicating whether the private key is printed. | `--private` | 
./polygon-edge polybft-secrets --insecure --data-dir test-chain- --num 4
Output example ↓ 
[WARNING: INSECURE LOCAL SECRETS - SHOULD NOT BE RUN IN PRODUCTION]

[SECRETS GENERATED]
network-key, validator-key, validator-bls-key

[SECRETS INIT]
Public key (address) = 0x61324166B0202DB1E7502924326262274Fa4358F
BLS Public key       = 06d8d9e6af67c28e85ac400b72c2e635e83234f8a380865e050a206554049a222c4792120d84977a6ca669df56ff3a1cf1cfeccddb650e7aacff4ed6c1d4e37b055858209f80117b3c0a6e7a28e456d4caf2270f430f9df2ba37221f23e9bbd313c9ef488e1849cc5c40d18284d019dde5ed86770309b9c24b70ceff6167a6ca
Node ID              = 16Uiu2HAmMYyzK7c649Tnn6XdqFLP7fpPB2QWdck1Ee9vj5a7Nhg8

[WARNING: INSECURE LOCAL SECRETS - SHOULD NOT BE RUN IN PRODUCTION]

[SECRETS GENERATED]
network-key, validator-key, validator-bls-key

[SECRETS INIT]
Public key (address) = 0xFE5E166BA5EA50c04fCa00b07b59966E6C2E9570
BLS Public key       = 0601da8856a6d3d3bb0f3bcbb90ea7b8c0db8271b9203e6123c6804aa3fc5f810be33287968ca1af2be11839516850a6ffef2337d99e679b7531efbbea2e3bf727a053c0cbede71da3d5f489b6ad862ccd8bb0bfb7fa379e3395d3b1142594a73020e87d63c298a3a4eba0ace65727f8659bab6389b9448b72512db72bbe937f
Node ID              = 16Uiu2HAmLXVapjR2Yx3B1taCmHnckQ1ph2xrawBjW2kvSErps9CX

[WARNING: INSECURE LOCAL SECRETS - SHOULD NOT BE RUN IN PRODUCTION]

[SECRETS GENERATED]
network-key, validator-key, validator-bls-key

[SECRETS INIT]
Public key (address) = 0x9aBb8441A12d4FD8D505C3fc50cDdc45E0df2b1e
BLS Public key       = 17c26d9d91dddc3c1318b20a1ddb3322ea1f4e4415c27e9011d706e7407eed672837173d1909cbff6ccdfd110af3b18bdfea878e8120fdb5bae70dc7a044a2f40aa8f118b41704896f474f80fff52d9047fa8e4a464ac86f9d05a0220975d8440e20c6307d866137053cabd4baf6ba84bfa4a22f5f9297c1bfc2380c23535210
Node ID              = 16Uiu2HAmGskf5sZ514Ab4SHTPuw8RRBQudyrU211wn3P1knRz9Ed

[WARNING: INSECURE LOCAL SECRETS - SHOULD NOT BE RUN IN PRODUCTION]

[SECRETS GENERATED]
network-key, validator-key, validator-bls-key

[SECRETS INIT]
Public key (address) = 0xCaB5AAC79Bebe326e0c80d72b5662E73f5D8ea56
BLS Public key       = 1d7bb7d44a2f0ebeae2f4380f88188080de34635d78a36647f0704c7b70de7291e2e3b9a1ef699a078c6cd9bb816ea2917c2c2fc699c6248f1f7812a167caf7e15361ec16df56d194768d57c79897c681c96f4321651464f7b577d08083d8b67213a1e29dc8495d8389e6cbd85fdd738c402a1801198b57b302e0e00dfaf1247
Node ID              = 16Uiu2HAm42EFMhJPGcMRFHPaWWxBzoEsWRbGxJnBHMu4VFojg99U

:::info Example with AWS Secrets

Prerequisites

  1. You need to have AWS CLI installed and configured on your machine.
  2. An AWS SSO account with the right permissions to access the SSM Parameter Store is required.

Step 1: AWS SSO Login

The first step is to log in to your AWS SSO account. In your terminal, run the following command:

aws sso login

Follow the prompts to complete the login process.

Step 2: Create Config.json File

Next, create a config.json file within your polygon-edge directory with the following contents:

{
  "Type": "aws-ssm",
  "Name": "validator1",
  "Extra": {
    "region": "us-west-2",
    "ssm-parameter-path": "/test" 
  }
}

Ensure to replace the "Name" value with the name you wish to use for your validator, and the "ssm-parameter-path" with the path in AWS SSM Parameter Store where your parameters will be stored.

Step 3: Run the Secret Generation Command

To generate the necessary secrets for your validator node, run the polybft-secrets command. In your terminal, input:

go run main.go polybft-secrets --config config.json

This will generate the secrets and store them in the AWS SSM Parameter Store as defined in your config.json file.

Step 4: Check Outputs in AWS SSM Parameter Store

Check your AWS SSM Parameter Store to verify that the secrets have been generated successfully. This can be done via the AWS console.

Note: In this tutorial, the example shown generated the following secrets: network-key, validator-key, and validator-bls-key. Your output will also show the public key (address), BLS public key, and Node ID.

:::

Understand the Generated Secrets

The generated secrets include the following information for each validator node:

  • ECDSA Private and Public Keys: These keys are used to sign and verify transactions on the blockchain.
  • BLS Private and Public Keys: These keys are used in the Byzantine fault-tolerant (BFT) consensus protocol to aggregate and verify signatures efficiently.
  • P2P Networking Node ID: This is a unique identifier for each validator node in the network, allowing them to establish and maintain connections with other nodes.

The secrets output can be retrieved again if needed by running the following command: ./polygon-edge polybft-secrets --data-dir test-chain-X/

2. Next Steps

As the next step, navigate to the Configure a New Childchain deployment guide. This will enable you to generate a new genesis file and define the initial validator set, facilitating the setup and configuration of the childchain's initial state.