Besu

Chapter 10: Besu - Enterprise Ethereum Client

Overview

Besu is an enterprise-grade Ethereum client developed by Hyperledger. Written in Java, it’s designed for organizations requiring permissioned networks, private transactions, and enterprise-level security features. Besu supports both public and private blockchain networks.

10.1 What is Besu?

┌─────────────────────────────────────────────────────────────────────────────┐
│                            BESU OVERVIEW                                        │
├─────────────────────────────────────────────────────────────────────────────┤
│                                                                              │
│   ┌─────────────────────────────────────────────────────────────────┐      │
│   │                      BESU CLIENT                                  │      │
│   │                                                                  │      │
│   │   ┌─────────────┐  ┌─────────────┐  ┌─────────────┐           │      │
│   │   │   Public   │  │  Permission │  │   Privacy   │           │      │
│   │   │   Networks │  │   Networks  │  │  (Private)  │           │      │
│   │   └─────────────┘  └─────────────┘  └─────────────┘           │      │
│   │                                                                  │      │
│   │   ┌─────────────┐  ┌─────────────┐  ┌─────────────┐           │      │
│   │   │  Ethereum  │  │   Consensus │  │   Standard  │           │      │
│   │   │   Mainnet  │  │   (IBFT)    │  │    EVM      │           │      │
│   │   └─────────────┘  └─────────────┘  └─────────────┘           │      │
│   └─────────────────────────────────────────────────────────────────┘      │
│                                                                              │
│   Key Characteristics:                                                      │
│   ━━━━━━━━━━━━━━━━━━━━━                                                      │
│   • Open source (Apache 2.0)                                               │
│   • Written in Java                                                         │
│   • Enterprise-focused                                                      │
│   • Supports public and private networks                                    │
│   • Built-in permissioning                                                 │
│                                                                              │
└─────────────────────────────────────────────────────────────────────────────┘

Comparison with Other Clients

Feature	Besu	Geth	Erigon	Nethermind
Language	Java	Go	Go	C#
License	Apache 2.0	LGPL	GPL	GPL
Enterprise	✅	❌	❌	✅
Privacy	✅	Limited	❌	✅
Permissioning	✅	❌	❌	❌
Snap Sync	❌	✅	✅	✅

10.2 Installation

Prerequisites

# Install Java (required)
# Ubuntu/Debian
sudo apt update
sudo apt install openjdk-17-jdk

# Verify Java
java --version

# Check memory
free -h

Binary Installation

# Download latest release
wget https://github.com/hyperledger/besu/releases/download/23.10.2/besu-23.10.2.tar.gz

# Extract
tar -xzf besu-23.10.2.tar.gz

# Create symbolic link
sudo ln -s /path/to/besu-23.10.2/bin/besu /usr/local/bin/besu

# Verify installation
besu --version

Docker Installation

# Pull image
docker pull hyperledger/besu:latest

# Run container
docker run -d \
  --name besu-node \
  -p 30303:30303 \
  -p 8545:8545 \
  -v /data/besu:/data \
  hyperledger/besu:latest \
  --network=mainnet \
  --data-path=/data \
  --rpc-http-enabled=true

# Docker Compose
cat > docker-compose.yml << EOF
version: '3.8'
services:
  besu:
    image: hyperledger/besu:latest
    container_name: besu-node
    ports:
      - "30303:30303"
      - "8545:8545"
    volumes:
      - ./data:/data
    environment:
      - BESU_OPTS=-Xmx2g
    command: [
      "--network=mainnet",
      "--data-path=/data",
      "--rpc-http-enabled=true",
      "--rpc-http-cors-origins=*",
      "--host-allowlist=*"
    ]
EOF

10.3 Running Besu

Quick Start

# Start on Ethereum Mainnet
besu --network=mainnet

# Start on Goerli Testnet
besu --network=goerli

# Start on Sepolia Testnet
besu --network=sepolia

RPC Node Configuration

# Full-featured RPC node
besu \
  --network=mainnet \
  --data-path=/data/besu \
  --rpc-http-enabled=true \
  --rpc-http-host=0.0.0.0 \
  --rpc-http-port=8545 \
  --rpc-http-api=ETH,NET,WEB3,DEBUG,TRACE \
  --rpc-http-cors-origins="*" \
  --ws-enabled=true \
  --ws-host=0.0.0.0 \
  --ws-port=8546 \
  --ws-api=ETH,NET,WEB3 \
  --p2p-enabled=true \
  --p2p-host=0.0.0.0 \
  --p2p-port=30303 \
  --max-peers=50 \
  --metrics-enabled=true \
  --metrics-host=0.0.0.0 \
  --metrics-port=9545

Configuration File

network: "mainnet"
data-path: "/data/besu"

rpc-http:
  enabled: true
  host: "0.0.0.0"
  port: 8545
  apis: ["ETH","NET","WEB3","DEBUG","TRACE"]
  cors-allowed-origins: ["*"]

ws:
  enabled: true
  host: "0.0.0.0"
  port: 8546

p2p:
  enabled: true
  host: "0.0.0.0"
  port: 30303

metrics:
  enabled: true
  host: "0.0.0.0"
  port: 9545

# Sync mode
sync-mode: "FAST"

# Genesis
# Besu uses default genesis for known networks

10.4 Key Enterprise Features

Permissioning

┌─────────────────────────────────────────────────────────────────┐
│                    BESU PERMISSIONING                                │
├─────────────────────────────────────────────────────────────────┤
│                                                                  │
│   Besu provides three types of permissioning:                    │
│                                                                  │
│   ┌─────────────────────────────────────────────────────────┐  │
│   │  ONCHAIN PERMISSIONING                                   │  │
│   │  ━━━━━━━━━━━━━━━━━━━━━                                   │  │
│   │  - Smart contract-based                                 │  │
│   │  - Network permissioning contract                       │  │
│   │  - Node permissioning contract                         │  │
│   │  - Account permissioning contract                      │  │
│   └─────────────────────────────────────────────────────────┘  │
│                              │                                   │
│                              ▼                                   │
│   ┌─────────────────────────────────────────────────────────┐  │
│   │  OFFCHAIN PERMISSIONING                                 │  │
│   │  ━━━━━━━━━━━━━━━━━━━━                                   │  │
│   │  - Local permission file                               │  │
│   │  - /etc/besu/permissions_config.toml                   │  │
│   │  - Immediate effect without onchain transactions         │  │
│   └─────────────────────────────────────────────────────────┘  │
│                                                                  │
└─────────────────────────────────────────────────────────────────┘

Permissioning Configuration

# Enable onchain permissioning
besu \
  --permissions-nodes-enabled=true \
  --permissions-accounts-enabled=true \
  --permissions-contracts-enabled=true \
  --permissions-contract-address=0x000... \
  --permissions-nodes-contract-address=0x000...

# Enable offchain permissioning
besu \
  --permissions-nodes-enabled=true \
  --permissions-nodes-config-file=/etc/besu/nodes-permissions.json

# nodes-permissions.json
{
  "nodes": [
    {
      "enode": "enode://...",
      "nodeId": "..."
    }
  ]
}

Privacy Features

# Enable privacy
besu \
  --privacy-enabled=true \
  --privacy-marker-transaction-signing-key-file=/path/to/key \
  --privacy-public-key-file=/path/to/public-key

# Private transaction groups
besu \
  --privacy-group-type=ONCHAIN \
  --priva-cy-enabled=true

10.5 Monitoring and Management

Prometheus Metrics

# Enable metrics
besu \
  --metrics-enabled=true \
  --metrics-host=0.0.0.0 \
  --metrics-port=9545

# Important metrics to monitor
# - besu_blockchain_height
# - besu_sync_combined_peers
# - besu_transaction_pool_transactions
# - besu_vm_execution_time
# - besu_process_memory

JSON-RPC API

# Check sync status
curl -X POST http://localhost:8545 \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_syncing","params":[],"id":1}'

# Get block number
curl -X POST http://localhost:8545 \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}'

# Get peers
curl -X POST http://localhost:8545 \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"net_peerCount","params":[],"id":1}'

10.6 Interview Questions

Question	Answer
What is Besu?	Enterprise Ethereum client by Hyperledger, written in Java
What makes Besu enterprise-friendly?	Permissioning, privacy features, enterprise support
What is Besu’s consensus mechanism?	IBFT2 (Istanbul Byzantine Fault Tolerant)
Does Besu support snap sync?	No, uses fast sync instead
What programming language is Besu written in?	Java

Summary

Besu is an enterprise-grade Ethereum client
Excellent for permissioned networks
Built-in permissioning and privacy features
Supports both public and private networks
Good choice for enterprise use cases

Next Chapter

In Chapter 11: Reth - Rust Ethereum Client, we’ll explore the Rust-based Ethereum client.

Last Updated: 2026-02-20