Run Ethereum PBS With Multi-Builders: A Guide

by Kenji Nakamura 46 views

Hey guys! Ever wanted to dive into the world of private Ethereum chains and play around with multiple builders? It's super cool, especially if you're into mev and PBS. Today, we're going to explore how to use the ethereum-package to set up a private Ethereum chain with multiple builders. We'll break down the steps, tackle the challenges, and get you up and running in no time!

Understanding the Challenge

So, you've already got a private Ethereum network running using the ethereum-package, which is awesome! You probably used a command like this:

kurtosis run --enclave my-testnet github.com/ethpandaops/ethereum-package --args file mev.yaml

And you've configured it for mev with something like mev_type: flashbots in your mev.yaml file. The thing is, by default, this setup usually spins up a single relay and a single builder. That's a great start, but what if you want to simulate a more complex environment with multiple builders? That’s where things get interesting!

The main challenge here is configuring the ethereum-package to support multiple builders. You might be wondering how to tweak the parameters or what magic incantations to use with the kurtosis service add my-enclave reth-builder command. Don't worry, we'll figure this out together.

Diving into the Solution: Setting up Multi-Builder PBS

To get multiple builders running, we need to dive into the configuration and understand how the ethereum-package works under the hood. We’ll focus on a few key areas:

  1. Configuration Files: Understanding the mev.yaml (or similar) file.
  2. Kurtosis Commands: Using kurtosis service add effectively.
  3. Networking: Ensuring the builders can communicate with the relay and the Ethereum nodes.

Let's break these down step by step.

1. Configuration Files: The Heart of Your Setup

The mev.yaml file (or whatever you named your config file) is where the magic happens. This file tells the ethereum-package how to set up your network. It includes details about the number of nodes, the type of mev setup, and, crucially, the builder configurations. To run a PBS private chain with multi-builders, you'll need to modify this file to specify multiple builder services.

First, let's look at a basic mev.yaml setup. It might look something like this:

mev_type: flashbots
relay:
  count: 1
builder:
  count: 1

This configuration tells the ethereum-package to create one relay and one builder. To add more builders, you might think you can just increase the builder.count, but it's not quite that simple. We need to define each builder individually to ensure they are properly configured and can operate independently.

Instead of a simple count, you’ll likely need to define a list of builders, each with its own configuration. This might include the builder's name, the image to use, and any specific command-line arguments. Here’s an example of how you might structure your mev.yaml to include multiple builders:

mev_type: flashbots
relay:
  count: 1
builders:
  - name: builder1
    image: "my-builder-image:latest" # Replace with your builder image
    args: ["--some-arg", "some-value"]
  - name: builder2
    image: "my-builder-image:latest"
    args: ["--another-arg", "another-value"]

In this example, we’ve replaced the simple builder section with a builders list. Each entry in the list represents a builder, and you can specify different images and arguments for each. This gives you the flexibility to run different builder implementations or configurations simultaneously. Remember, the key is to define each builder explicitly.

2. Kurtosis Commands: Adding Services Like a Pro

Now that we've got our configuration file sorted, let's talk about Kurtosis commands. The kurtosis service add command is your friend here. It allows you to add services to your running enclave (your private network). However, to add builders effectively, we need to understand how Kurtosis manages services and how they interact within the network.

The basic syntax for adding a service is:

kurtosis service add <enclave-name> <service-name> <image-name> --args <args>

For example, you tried something like:

kurtosis service add my-enclave reth-builder

But this command alone isn't enough. You need to provide more information, such as the image to use for the builder and any specific arguments it needs. This is where the configuration in your mev.yaml comes into play.

If you've defined your builders in the mev.yaml as shown earlier, you might need a script or a series of commands to add each builder. Here’s a conceptual example of how you might do it:

# Assuming you have a way to parse your mev.yaml (e.g., using yq)

for builder in $(yq e '.builders[]' mev.yaml); do
  name=$(yq e '.name' <<< "$builder")
  image=$(yq e '.image' <<< "$builder")
  args=$(yq e '.args | @json' <<< "$builder")

  kurtosis service add my-enclave "$name" "$image" --args "$args"
done

This script (or similar logic) reads your mev.yaml, extracts the builder configurations, and then uses kurtosis service add to add each builder to your enclave. This approach ensures that each builder is added with its specific configuration, as defined in your mev.yaml.

3. Networking: Making Sure Everyone Can Talk

Networking is the unsung hero of any distributed system. In our case, we need to ensure that all the builders can communicate with the relay and the Ethereum nodes. Kurtosis handles a lot of the networking for you, but it’s essential to understand the basics to troubleshoot any issues.

When you add a service using kurtosis service add, Kurtosis automatically creates a network within the enclave. Services can communicate with each other using their service names as hostnames. For example, if you have a relay service named my-relay and a builder service named builder1, builder1 can communicate with my-relay by using my-relay as the hostname.

However, you might need to configure specific ports and protocols depending on the services you are using. For example, the relay might need to expose a specific port for builders to submit transactions. You can configure these details in your mev.yaml or through command-line arguments when adding the service.

It’s crucial to ensure that your builders are configured to connect to the correct endpoints for the relay and the Ethereum nodes. This might involve setting environment variables or command-line arguments when adding the service. For instance, you might need to specify the relay’s address and port in the builder’s configuration.

Putting It All Together: A Complete Example

Let's recap and put together a complete example to illustrate how to run a private Ethereum chain with multiple builders using the ethereum-package.

  1. Create your mev.yaml: Define your builders, relay, and any other services you need. Here’s an example:

    mev_type: flashbots
relay:
  count: 1
builders:
  - name: builder1
    image: "my-builder-image:latest"
    args: ["--relay-url", "http://my-relay:8080"]
  - name: builder2
    image: "my-builder-image:latest"
    args: ["--relay-url", "http://my-relay:8080"]

  2. Run the ethereum-package: Start your private network using the kurtosis run command:

    kurtosis run --enclave my-testnet github.com/ethpandaops/ethereum-package --args file mev.yaml

  3. Add the builders: If the ethereum-package doesn't automatically add the builders (depending on its implementation), you can use a script like the one we discussed earlier to add them manually.

  4. Verify the setup: Check that all services are running and that the builders can communicate with the relay. You can use kurtosis service logs to view the logs for each service and ensure there are no connection errors.

Troubleshooting Common Issues

Even with the best planning, things can sometimes go wrong. Here are a few common issues you might encounter and how to troubleshoot them:

  • Builders can't connect to the relay: Double-check the relay URL in your builder configurations. Ensure that the relay is running and accessible from the builders. Use kurtosis service logs to check for any errors in the relay logs.
  • Configuration errors: If your mev.yaml is not correctly formatted, Kurtosis might fail to start the network or add services. Use a YAML validator to check your file for syntax errors. Ensure that all required fields are present and correctly configured.
  • Image issues: If Kurtosis can't pull the builder image, check that the image name is correct and that the image is available in the registry. If you're using a private registry, ensure that Kurtosis has the necessary credentials to access it.

Conclusion: Your Journey to Multi-Builder PBS

Running a private Ethereum chain with multiple builders using the ethereum-package is a fantastic way to explore mev and PBS. It might seem daunting at first, but by understanding the configuration files, Kurtosis commands, and networking aspects, you can set up a powerful testing environment. Remember, the key is to define each builder explicitly and ensure they can communicate with the relay and the Ethereum nodes.

So, go ahead, experiment, and build something awesome! And if you run into any snags, don't hesitate to ask for help in the ethpandaops community. Happy building, guys!