Skip to main content
Version: 1.30.0

Private networks

This guide will walk you through using Kurtosis ethereum-package to spin up a private, proof-of-stake (PoS) Ethereum devnet with three full Ethereum nodes locally over Docker. At the end of the guide, you will learn how to scale up your testnet on Kubernetes as well as enable optional services for your local testnet, such as network observability tools (e.g., Grafana, Prometheus) and Flashbot's mev-boost infrastructure to simulate MEV workflows.

Step 1: Prerequisites

Before you begin, ensure you have Kurtosis CLI and Docker installed. The ethereum-package is a Kurtosis environment definition known as a package. For more info about Kurtosis, see the Kurtosis docs.

Step 2: Configure your network

Next, in your home directory, create a file with the name network_params.json and populate it with the following contents:

network_params.json
{
"participants": [
{
"el_client_type": "nethermind",
"el_client_image": "nethermind/nethermind:latest",
"cl_client_type": "lighthouse",
"cl_client_image": "sigp/lighthouse:latest",
"count": 1
},
{
"el_client_type": "nethermind",
"el_client_image": "nethermind/nethermind:latest",
"cl_client_type": "teku",
"cl_client_image": "consensys/teku:latest",
"count": 1
},
{
"el_client_type": "nethermind",
"el_client_image": "nethermind/nethermind:latest",
"cl_client_type": "lodestar",
"cl_client_image": "chainsafe/lodestar:next",
"count": 1
}
],
"mev_type": "None",
"launch_additional_services": false
}

As you can see above, you have effectively created a network configuration file that Kurtosis will use to pass in the necessary parameters at runtime for your network. Notice that the participant key describes the execution and consensus client pairing desired for each full node and how many nodes of that type to instantiate.

There are many other configurations and flags you can use, including metrics and observability tools (e.g., Grafana, Prometheus, etc). For all supported options, see the ethereum-package configuration.

Step 3: Deploy

Finally, once you have saved the network_params.json file, it is time to deploy the private net:

kurtosis run github.com/ethpandaops/ethereum-package "$(cat ~/network_params.json)"

Kurtosis will use the ethereum-package environment definition and your custom network configuration (defined in network_params.json) to spin up your network. Kurtosis will first spin up an enclave (i.e., an ephemeral, isolated environment) and begin to configure and instantiate the nodes in your network. In the end, Kurtosis will print the services running in your enclave that form your private testnet alongside all the container ports and files that were generated and used to start up the private testnet.

Here is a sample output:

INFO[2023-09-01T16:10:45-04:00] ====================================================
INFO[2023-09-01T16:10:45-04:00] || Created enclave: timid-knoll ||
INFO[2023-09-01T16:10:45-04:00] ====================================================
Name: timid-knoll
UUID: 939dfb5d59b0
Status: RUNNING
Creation Time: Fri, 01 Sep 2023 16:08:57 EDT

========================================= Files Artifacts =========================================
UUID Name
a876b06035b7 1-lighthouse-nethermind-0-63
87955ef69845 2-teku-nethermind-64-127
4f77377da494 3-lodestar-nethermind-128-191
9734313101e3 cl-genesis-data
4164ed5c594c el-genesis-data
a49a3d2774b5 genesis-generation-config-cl
16fcc4f96236 genesis-generation-config-el
5fc72346f646 geth-prefunded-keys
96ae153a0b51 prysm-password

========================================== User Services ==========================================
UUID Name Ports Status
f369802ad2ae cl-1-lighthouse-nethermind http: 4000/tcp -> http://127.0.0.1:49894 RUNNING
metrics: 5054/tcp -> http://127.0.0.1:49892
tcp-discovery: 9000/tcp -> 127.0.0.1:49893
udp-discovery: 9000/udp -> 127.0.0.1:64949
5e14eb26ef45 cl-1-lighthouse-nethermind-validator http: 5042/tcp -> 127.0.0.1:49895 RUNNING
metrics: 5064/tcp -> http://127.0.0.1:49896
fed533d0e143 cl-2-teku-nethermind http: 4000/tcp -> 127.0.0.1:49899 RUNNING
metrics: 8008/tcp -> 127.0.0.1:49897
tcp-discovery: 9000/tcp -> 127.0.0.1:49898
udp-discovery: 9000/udp -> 127.0.0.1:55521
69cd832de246 cl-3-lodestar-nethermind http: 4000/tcp -> 127.0.0.1:49903 RUNNING
metrics: 8008/tcp -> 127.0.0.1:49901
tcp-discovery: 9000/tcp -> 127.0.0.1:49902
udp-discovery: 9000/udp -> 127.0.0.1:50507
75e3eec0c7d1 cl-3-lodestar-nethermind-validator metrics: 8008/tcp -> 127.0.0.1:49904 RUNNING
e10c3f07e0e0 el-1-nethermind-lighthouse engine-rpc: 8551/tcp -> 127.0.0.1:49872 RUNNING
rpc: 8545/tcp -> 127.0.0.1:49870
tcp-discovery: 30303/tcp -> 127.0.0.1:49869
udp-discovery: 30303/udp -> 127.0.0.1:64508
ws: 8546/tcp -> 127.0.0.1:49871
c6a28d3136fe el-2-nethermind-teku engine-rpc: 8551/tcp -> 127.0.0.1:49873 RUNNING
rpc: 8545/tcp -> 127.0.0.1:49875
tcp-discovery: 30303/tcp -> 127.0.0.1:49874
udp-discovery: 30303/udp -> 127.0.0.1:52495
ws: 8546/tcp -> 127.0.0.1:49876
2fae3b3c41d3 el-3-nethermind-lodestar engine-rpc: 8551/tcp -> 127.0.0.1:49890 RUNNING
rpc: 8545/tcp -> 127.0.0.1:49888
tcp-discovery: 30303/tcp -> 127.0.0.1:49891
udp-discovery: 30303/udp -> 127.0.0.1:62119
ws: 8546/tcp -> 127.0.0.1:49889
403cafe8416e prelaunch-data-generator-cl-genesis-data <none> RUNNING
ebea71008cf4 prelaunch-data-generator-el-genesis-data <none> RUNNING

And that is it! You now have a 3-node, private Ethereum devnet with Nethermind/Lodestar, Nethermind/Teku, and Nethermind/Lighthouse execution and consensus client combinations.

Notice how, at the end, Kurtosis will print out the contents of your enclave, which includes both the various files artifacts and services that form your network. Kurtosis also maps the container ports to ephemeral local ports on your machine.

Genesis data was generated using this genesis-generator to bootstrap the execution and consensus clients for each node. The end result will be a private testnet with nodes deployed as Docker containers in an ephemeral, isolated environment on your machine called an enclave.

Kurtosis packages are modular, reproducible, and will work over Docker or Kubernetes. Read on to learn about additional services and configurations you may want to add to your private network.

Step 4: Optional workflows

This section briefly covers some optional configurations for your private devnet that are commonly used for validating and testing node-level behavior.

Simulating MEV workflows with mev-boost

The ethereum-package can simulate out-of-protocol Proposer Builder Separation (PBS) workflows using Flashbot's mev-boost infrastructure. With a single flag, you can configure your network's validators to be instantiated with mev-boost and be registered with a relayer to receive payloads from builders.

To enable this in your network_params.json file, set "mev_type": to "full" or "mock".

To learn more about how the mev-boost infrastructure works with your private network, check out this guide.

Observability tools

The ethereum-package comes out of the box with a few observability tools, including:

To add your own custom Grafana dashboard template, fork the ethereum-package repository and add your configuration here.

Deploying on Kubernetes

As mentioned earlier, Kurtosis packages (i.e. environment definitions) are portable and will work the same way over Docker or on Kubernetes. Should you require a larger scale devnet, Kurtosis can deploy any package, including the ethereum-package on Kubernetes, see Running Kurtosis in Kubernetes.

Questions and feedback

If you need help with your Nethermind full node in the private devnet, please don't hesitate to contact the Kurtosis team on GitHub or Discord.