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Private Chain Setup

Setting up a private Circle Layer blockchain network enables enterprises and development teams to create isolated environments for testing, development, and internal applications while maintaining full control over the network.

Overview​

A private Circle Layer chain provides:

  • Complete Control: Full control over validator nodes and network parameters
  • Privacy: Isolated network not connected to public testnet/mainnet
  • Customization: Ability to modify consensus parameters, gas limits, and block times
  • Development Environment: Perfect for testing and development workflows
  • Enterprise Solutions: Internal blockchain applications and processes

Prerequisites​

System Requirements​

Minimum Requirements:

  • CPU: 4+ cores
  • RAM: 8GB+
  • Storage: 100GB+ SSD
  • Network: Stable internet connection
  • OS: Ubuntu 20.04+, CentOS 8+, or macOS 12+

Recommended for Production:

  • CPU: 8+ cores
  • RAM: 16GB+
  • Storage: 500GB+ SSD
  • Network: High-speed connection with low latency
  • Backup: Redundant storage solutions

Software Dependencies​

# Ubuntu/Debian
sudo apt update
sudo apt install -y curl wget git build-essential golang-go

# CentOS/RHEL
sudo yum update
sudo yum install -y curl wget git gcc gcc-c++ make golang

# macOS
brew install curl wget git go

Installation​

1. Download and Compile Circle Layer​

# Clone the Circle Layer blockchain source code
git clone https://github.com/circlelayer/testnet-core-blockchain.git

# Navigate to the project directory
cd Core-Blockchain

# Compile the geth binary
make geth

After compilation is completed, the generated binary will be in the build/bin folder.

2. Verify Installation​

# Check if compilation was successful
./build/bin/geth --help

Quick Start​

1. Prepare Validator Account(s)​

According to the number of miner nodes, prepare corresponding validator account(s).

# Create directory for private chain
mkdir -p ~/private-circlelayer
cd ~/private-circlelayer

# Create a new account
./path/to/Core-Blockchain/build/bin/geth account new --datadir data

# Store password in a text file for convenience
echo "your-password" > password.txt

After creating an account, note the address of the new account. You can also find it in the UTC-** file under the data/keystore path.

2. Configure Genesis​

Create a custom genesis.json configuration:

{
  "config": {
    "chainId": 12345,
    "homesteadBlock": 0,
    "eip150Block": 0,
    "eip150Hash": "0x0000000000000000000000000000000000000000000000000000000000000000",
    "eip155Block": 0,
    "eip158Block": 0,
    "byzantiumBlock": 0,
    "constantinopleBlock": 0,
    "petersburgBlock": 0,
    "istanbulBlock": 0,
    "muirGlacierBlock": 0,
    "berlinBlock": 0,
    "londonBlock": 0,
    "congress": {
      "period": 3,
      "epoch": 100
    }
  },
  "nonce": "0x0",
  "timestamp": "0x683698D4",
  "extraData": "0x00000000000000000000000000000000000000000000000000000000000000007b3a3e7c7a6b4d8e2f1a9c5d7b9e2f4a6c8e1d3f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
  "gasLimit": "0xffffffffffffffff",
  "difficulty": "0x1",
  "mixHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
  "coinbase": "0x7b3a3e7c7a6b4d8e2f1a9c5d7b9e2f4a6c8e1d3f",
  "number": "0x0",
  "gasUsed": "0x0",
  "parentHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
  "alloc": {
    "0x7b3a3e7c7a6b4d8e2f1a9c5d7b9e2f4a6c8e1d3f": {
      "balance": "1000000000000000000000000000"
    }
  }
}

Note: Replace 0x7b3a3e7c7a6b4d8e2f1a9c5d7b9e2f4a6c8e1d3f with your actual validator address in both extraData and alloc sections.

3. Create Genesis Block​

After generating the genesis.json file, execute the following command to generate the genesis block:

./path/to/Core-Blockchain/build/bin/geth init genesis.json --datadir data

4. Start Private Node​

# Start the private chain
./path/to/Core-Blockchain/build/bin/geth \
    --datadir ./data \
    --networkid 12345 \
    --http \
    --http.addr "0.0.0.0" \
    --http.port 8545 \
    --http.api "eth,net,web3,personal,miner" \
    --ws \
    --ws.addr "0.0.0.0" \
    --ws.port 8546 \
    --ws.api "eth,net,web3" \
    --mine \
    --miner.threads 1 \
    --unlock "0x7b3a3e7c7a6b4d8e2f1a9c5d7b9e2f4a6c8e1d3f" \
    --password password.txt

Advanced Configuration​

Multi-Node Setup​

Use the same genesis.json file for initializing each node. Then use the geth console to manage peer connections.

Node 1 (Bootnode)​

# Start first node
./path/to/Core-Blockchain/build/bin/geth \
    --datadir ./node1 \
    --networkid 12345 \
    --port 30303 \
    --http \
    --http.port 8545 \
    --mine

Node 2 (Peer)​

# Start second node
./path/to/Core-Blockchain/build/bin/geth \
    --datadir ./node2 \
    --networkid 12345 \
    --port 30304 \
    --http \
    --http.port 8546

Connect Nodes​

# Connect to first node console
./path/to/Core-Blockchain/build/bin/geth attach http://localhost:8545

# Get node info
admin.nodeInfo.enode

# On second node, add the first node as peer
admin.addPeer("enode://[bootnode-enode-url]@127.0.0.1:30303")

Configuration File Setup​

For production deployments, create a config.toml file:

[Eth]
SyncMode = "fast"
DiscoveryURLs = []
TrieCleanCacheRejournal = 300000000000

[Eth.Miner]
GasFloor = 8000000
GasCeil = 8000000
GasPrice = 0
Recommit = 3000000000
Noverify = false

[Eth.TxPool]
Locals = []
NoLocals = false
Journal = "transactions.rlp"
Rejournal = 3600000000000
PriceLimit = 1
PriceBump = 10
AccountSlots = 16
GlobalSlots = 4096
AccountQueue = 64
GlobalQueue = 1024
Lifetime = 10800000000000

[Node]
DataDir = "/data/circlelayer/data"
InsecureUnlockAllowed = true
NoUSB = true
IPCPath = "geth.ipc"
HTTPHost = "0.0.0.0"
HTTPPort = 8545
HTTPCors = ["*"]
HTTPVirtualHosts = ["*"]
HTTPModules = ['eth', 'net', 'web3']

WSHost = "0.0.0.0"
WSPort = 8546
WSModules = ['eth', 'net', 'web3']

[Node.P2P]
MaxPeers = 50
NoDiscovery = false
ListenAddr = "32668"
EnableMsgEvents = false

[Node.HTTPTimeouts]
ReadTimeout = 30000000000
WriteTimeout = 30000000000
IdleTimeout = 120000000000

Then start with the configuration file:

./path/to/Core-Blockchain/build/bin/geth --config config.toml

Network Connection​

By default, the node will attempt to connect to the mainnet. To connect to different networks:

  • Testnet: Add --testnet flag
  • Private Network: Use --networkid with your custom chain ID

Security Considerations​

  1. Private Keys: Store validator private keys securely
  2. Network Access: Restrict RPC access to trusted IPs
  3. Firewall: Configure appropriate firewall rules
  4. Backup: Regular backup of blockchain data and keys
  5. Monitoring: Implement monitoring for node health and performance

Troubleshooting​

Common Issues​

  1. Compilation Errors: Ensure Go is properly installed and version is compatible
  2. Network Connectivity: Check firewall and network configurations
  3. Genesis Mismatch: Ensure all nodes use the same genesis.json file
  4. Account Unlock: Verify password file and account permissions

Debug Mode​

To run with debug logging:

./path/to/Core-Blockchain/build/bin/geth --verbosity 4 [other-flags]

Additional Resources​