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Date of last update: August 8, 2022

Run Besu and Teku on the Merge testnet

You can test Besu as an execution client and Teku as a consensus client on the Kiln Merge testnet.

1. Install Besu and Teku

Install Besu and Teku.

Ensure you meet the prerequisites for the installation option you use. For example, you must have Java 11+ if using the Besu and Teku binary distributions.

Ensure you meet the system requirements for Besu on Mainnet.

2. Generate the shared secret

Run the following command:

openssl rand -hex 32 | tr -d "\n" > jwtsecret.hex

You will specify jwtsecret.hex when starting both Besu and Teku. This is a shared JWT secret the clients use to authenticate each other when using the Engine API.

3. Generate validator keys and stake ETH

If you’re running a validator client, create a test Ethereum address (you can do this in MetaMask). Fund this address with testnet ETH using the Kiln Faucet.

Note

If you’re unable to get ETH using the faucet, you can ask for help on the EthStaker Discord.

Generate validator keys and stake your testnet ETH for one or more validators using the Kiln Staking Launchpad.

Important

Save the password you use to generate each key pair in a .txt file. You should also have a .json file for each validator key pair.

4. Start Besu

Run the following command:

besu \
  --network=kiln              \
  --rpc-http-enabled=true     \
  --rpc-http-host="0.0.0.0"   \
  --rpc-http-cors-origins="*" \
  --rpc-ws-enabled=true       \
  --rpc-ws-host="0.0.0.0"     \
  --host-allowlist="*"        \
  --engine-host-allowlist="*" \
  --engine-rpc-port=8550      \
  --Xmerge-support=true       \
  --engine-jwt-secret=<path to jwtsecret.hex>

Specify the path to the jwtsecret.hex file generated in step 2 using the --engine-jwt-secret option.

See the --engine-* options for more information on running Besu as an execution client.

5. Start Teku

Open a new terminal window.

Beacon node only

To run Teku as a beacon node (without validator duties), run the following command:

teku \
  --data-path "datadir-teku"                   \
  --network kiln                               \
  --ee-endpoint http://localhost:8550          \
  --Xee-version kilnv2                         \
  --ee-jwt-secret-file <path to jwtsecret.hex> \
  --log-destination console                    \
  --rest-api-enabled=true                      \
  --p2p-discovery-bootnodes "enr:-Iq4QMCTfIMXnow27baRUb35Q8iiFHSIDBJh6hQM5Axohhf4b6Kr_cOCu0htQ5WvVqKvFgY28893DHAg8gnBAXsAVqmGAX53x8JggmlkgnY0gmlwhLKAlv6Jc2VjcDI1NmsxoQK6S-Cii_KmfFdUJL2TANL3ksaKUnNXvTCv1tLwXs0QgIN1ZHCCIyk"

Specify the path to the jwtsecret.hex file generated in step 2 using the --ee-jwt-secret-file option.

Beacon node and validator client

To run Teku as a beacon node and validator in a single process, run the following command:

teku \
  --data-path "datadir-teku"                                \
  --network kiln                                            \
  --ee-endpoint http://localhost:8550                       \
  --Xee-version kilnv2                                      \
  --ee-jwt-secret-file <path to jwtsecret.hex>              \
  --log-destination console                                 \
  --rest-api-enabled=true                                   \
  --validators-proposer-default-fee-recipient=<ETH address> \
  --validator-keys=<path to key file>:<path to mnemonic file>[,<path to key file>:<path to mnemonic file>,...] \
  --p2p-discovery-bootnodes "enr:-Iq4QMCTfIMXnow27baRUb35Q8iiFHSIDBJh6hQM5Axohhf4b6Kr_cOCu0htQ5WvVqKvFgY28893DHAg8gnBAXsAVqmGAX53x8JggmlkgnY0gmlwhLKAlv6Jc2VjcDI1NmsxoQK6S-Cii_KmfFdUJL2TANL3ksaKUnNXvTCv1tLwXs0QgIN1ZHCCIyk"

Specify:

See the Teku --validators-* options for more information on running Teku as a validator.

After starting Besu and Teku

After starting Besu and Teku, your node should start syncing and connecting to peers.

Example

2022-03-21 20:42:09.295-07:00 | EthScheduler-Timer-0 | INFO  | FullSyncTargetManager | No sync target, waiting for peers. Current peers: 0
2022-03-21 20:42:14.298-07:00 | EthScheduler-Timer-0 | INFO  | FullSyncTargetManager | No sync target, waiting for peers. Current peers: 0
2022-03-21 20:42:14.848-07:00 | nioEventLoopGroup-3-8 | INFO  | FullSyncTargetManager | No sync target, waiting for peers. Current peers: 4
2022-03-21 20:42:18.452-07:00 | nioEventLoopGroup-3-8 | INFO  | SyncTargetManager | Found common ancestor with peer Peer 0xab3a286b181721c794... at block 55127
2022-03-21 20:42:18.454-07:00 | nioEventLoopGroup-3-8 | INFO  | PipelineChainDownloader | PipelineChain download complete
2022-03-21 20:43:24.355 INFO  - Syncing     *** Target slot: 76092, Head slot: 2680, Remaining slots: 73412, Connected peers: 8
2022-03-21 20:43:36.363 INFO  - Syncing     *** Target slot: 76093, Head slot: 2879, Remaining slots: 73214, Connected peers: 10
2022-03-21 20:43:48.327 INFO  - Syncing     *** Target slot: 76094, Head slot: 3080, Remaining slots: 73014, Connected peers: 8
2022-03-21 20:44:00.339 INFO  - Syncing     *** Target slot: 76095, Head slot: 3317, Remaining slots: 72778, Connected peers: 6
2022-03-21 20:44:12.353 INFO  - Syncing     *** Target slot: 76096, Head slot: 3519, Remaining slots: 72577, Connected peers: 9

It may take up to multiple days for your validator to be activated and start proposing blocks.