Updated on July 29, 2020

Starting Hyperledger Besu

You can use Besu nodes for varying purposes, as described in the Overview. Nodes can connect to the Ethereum MainNet, public testnets such as Ropsten, or private networks.

Prerequisites

Besu Installed

Local block data

When connecting to a network other than the network previously connected to, you must either delete the local block data or use the --data-path option to specify a different data directory.

To delete the local block data, delete the database directory in the besu/build/distribution/besu-<version> directory.

Genesis configuration

Besu specifies the genesis configuration, and sets the network ID and bootnodes when connecting to MainNet, Goerli, Rinkeby, and Ropsten.

When you specify --network=dev, Besu uses the development mode genesis configuration with a fixed low difficulty. A node started with --network=dev has an empty bootnodes list by default.

The genesis files defining the genesis configurations are in the Besu source files.

To define a genesis configuration, create a genesis file (for example, genesis.json) and specify the file using the --genesis-file option.

Confirm node is running

If you started Besu with the --rpc-http-enabled option, use cURL to call JSON-RPC API methods to confirm the node is running.

Example

eth_chainId returns the chain ID of the network.

curl -X POST --data '{"jsonrpc":"2.0","method":"eth_chainId","params":[],"id":1}' localhost:8545

eth_syncing returns the starting, current, and highest block.

curl -X POST --data '{"jsonrpc":"2.0","method":"eth_syncing","params":[],"id":1}' localhost:8545

For example, after connecting to mainnet eth_syncing will return something similar to:

{
  "jsonrpc" : "2.0",
  "id" : 1,
  "result" : {
    "startingBlock" : "0x0",
    "currentBlock" : "0x2d0",
    "highestBlock" : "0x66c0"
  }
}

Run a node for testing

To run a node that mines blocks at a rate suitable for testing purposes:

besu --network=dev --miner-enabled --miner-coinbase=0xfe3b557e8fb62b89f4916b721be55ceb828dbd73 --rpc-http-cors-origins="all" --host-allowlist="*" --rpc-ws-enabled --rpc-http-enabled --data-path=/tmp/tmpDatdir

You can also use the following configuration file on the command line to start a node with the same options as above:

network="dev"
miner-enabled=true
miner-coinbase="0xfe3b557e8fb62b89f4916b721be55ceb828dbd73"
rpc-http-cors-origins=["all"]
host-allowlist=["*"]
rpc-ws-enabled=true
rpc-http-enabled=true
data-path="/tmp/tmpdata-path"

Caution

The following settings are a security risk in production environments:

Enabling the HTTP JSON-RPC service (--rpc-http-enabled) and setting --rpc-http-host to 0.0.0.0 exposes the RPC connection on your node to any remote connection.
Setting --host-allowlist to "*" allows JSON-RPC API access from any host.
Setting --rpc-http-cors-origins to "all" or "*" allows cross-origin resource sharing (CORS) access from any domain.

Run a node on Ropsten testnet

To run a node on Ropsten:

besu --network=ropsten

To run a node on Ropsten with the HTTP JSON-RPC service enabled and allow Remix to access the node:

besu  --network=ropsten --rpc-http-enabled --rpc-http-cors-origins "http://remix.ethereum.org"

Run a node on Rinkeby testnet

To run a node on Rinkeby specifying a data directory:

besu --network=rinkeby --data-path=<path>/<rinkebydata-path>

Where <path> and <rinkebydata-path> are the path and directory to save the Rinkeby chain data to.

Run a node on Goerli testnet

To run a node on Goerli specifying a data directory:

besu --network=goerli --data-path=<path>/<goerlidata-path>

Where <path> and <goerlidata-path> are the path and directory to save the Goerli chain data to.

Run a node on Ethereum MainNet

To run a node on the Ethereum MainNet:

besu

To run a node on MainNet with the HTTP JSON-RPC service enabled and available for localhost only:

besu --rpc-http-enabled