NeonEVM Proxy

This playbook sets up a dedicated Neon EVM proxy host. It's intended as a starting point for a new NeonEVM node operator.

Basic requirements

The NeonEVM proxy should best be run with a dedicated Solana RPC node. You will need to have minimal possible latency between your Solana RPC and the Neon EVM. Our recommended approach is to run the NeonEVM proxy on the same host as the Solana RPC node.

If you run the NeonEVM proxy on a separate node from your Solana RPC node, then you should ensure the following:

• Minimal latency between NeonEVM and the Solana node, ideally they should be on the same private or local network or at least within the same DC.
• No public access to the Solana RPC node and (ideally) no other Solana RPC traffic to the Neon EVM node: Since it is very easy to make a Solana RPC node fall behind the tip of the network, which would cause issues for the Neon EVM proxy we strongly recommend that you have a dedicated RPC node for Neon EVM.

Using a shared or public RPC node for NeonEVM is accordingly not recommended as there is too strong possibility that the node will have variable performance and therefore cause your Neon EVM proxy to fail to submit or confirm some of its transactions, which would mean that you risk loosing the benefits from processing those transactions.

If you don't want to run your own Solana RPC node but just want to be a Neon EVM operator, then Triton is one of several RPC providers in the Solana ecosystem that can provide you with a dedicated node to point your Neon EVM proxy to (see below for how to specify the Solana RPC url).

Hardware requirements

An RPC server requires at least the same specs as a Solana validator, but typically has higher requirements. For more information about hardware requirements, please see the Solana docs. In particular they recommend:

• 16 cores
• 256 gb memory

For the EVM proxy, the hardware requirements. NeonEVM recommends:

• 4 cores
• 16 gb memory

In sum, this suggest that a combined node running NeonEVM and the Solana RPC could have the following recommended specs:

• 16-24 cores of a recent processor Zen 2, Zen 3 or latest Cascade Lake Refresh Xeons
• 256 gb memory

A suitable processor might be EPYC 7443P or 7413P.

Considering the bandwidth requirements of Solana we recommend using a bare metal host rather than running on the cloud, as you will otherwise pay high egress fees as well as (potentially) see low performance due to the virtualization layer of cloud providers.

Software requirements

These deploys are built for Ansible 2.9 on Ubuntu 20.04 LTS. Any Debian-like Linux distribution you should work as well.

Dependencies:

• Docker Ansible Role
• PostgreSql Ansible Role
  • Configure high connection limit (e.g. 300) on Postgres

If you want to run Postgres in Docker please see https://github.com/rpcpool/neonevm-proxy-ansible/pull/2/files

Sample playbook

Before running the playbook, make sure you install the required roles:

ansible-galaxy install rpcpool.solana_rpc
ansible-galaxy install rpcpool.neonevm_proxy

To deploy the Neon EVM proxy with a Solana RPC node on the local machine, running on devnet:

- name: deploy rpc hosts
  remote_user: root
  hosts:
    - 127.0.0.1
  roles:
    - role: rpcpool.solana_rpc
      vars:
      solana_network: devnet
    - role: rpcpool.neonevm_proxy
      vars:
        neonevm_network: devnet

Full-ish example (missing some patches to postgres role):

- name: deploy rpc hosts
  remote_user: root
  hosts:
    - 127.0.0.1
  vars:
    neonevm_enabled: true
    solana_network: devnet
    neonevm_env:
      POSTGRES_HOST: 127.0.0.1
      # uncomment if you need to use non default port
      #PGPORT: 5433
      POSTGRES_DB: neonevm
      POSTGRES_USER: neonevm
      POSTGRES_PASSWORD: "<your-secure-password>"

    postgres_databases:
    - name: "{{ neonevm_env.POSTGRES_DB }}"

    postgres_users:
    - name: "{{ neonevm_env.POSTGRES_DB }}"
      password: "{{ neonevm_env.POSTGRES_PASSWORD }}"

  roles:
    - role: robertdebock.postgres
    - role: rpcpool.solana_rpc
    - role: rpcpool.neonevm_proxy

More details about the configuration of the Solana RPC node can be found here.

Neon EVM setup

Choosing an network

The main configuration variable is neonevm_network. Set this to mainnet, testnet or devnet. The default is devnet. This will set the neonevm CONFIG environment variable which will set the correct values for EVM_LOADER, COLLATERAL_POOL_BASE and ETH_TOKEN_MINT.

Setting the Solana RPC server

You also need to set neonevm_solana_rpc. This will default to our recommended version of running Solana on localhost - i.e. http://localhost:8899. If you want to run Neon EVM separate from the Solana node you can specify a different RPC URL in this variable.

Creating a custom config

You can create a custom config by specifying neonevm_env. For example to run Neon EVM on a local cluster specify the following:

neonevm_env:
    SOLANA_URL: http://localhost:8899
    CONFIG: local
    POSTGRES_DB: neonevm
    POSTGRES_USER: neonevm
    POSTGRES_PASSWORD: "<your-secure-password>"
    EVM_LOADER: deploy # not strictly required as this is the default value for 'CONFIG: local'
    COLLATERAL_POOL_BASE: deploy  # not strictly required as this is the default value for 'CONFIG: local'
    ETH_TOKEN_MINT: deploy # not strictly required as this is the default value for 'CONFIG: local'

More details about the environment variables here: https://docs.neon-labs.org/docs/proxy/operator_guide/#run-a-daemon

Neon EVM keypair

The playbook creates a new Neon EVM keypair by default located in /home/neonevm/neonevm-keypair.json. You need to fund this keypair for your EVM to work on the Solana chain. The keypair hash can be found in neonevm.pub in the deployment directory after the deploy has successfully completed. You can transfer funds to this key from any wallet.

To check the balance for a devnet node (assuming you have the Solana cli installed), you can always run solana balance -u devnet $(cat neonevm.pub). This wallet needs to be kept filled to cover the transaction fees for your proxy on devnet.

Getting devnet SOL

You'll need to fund the keypair used for Neon:

solana airdrop 10 $(cat neonevm.pub) --url https://api.devnet.solana.com

Creating the SPL token account

Before running your proxy fully you will also need to create an SPL token account to hold the Neon SPL tokens:

e.g.

spl-token create-account 89dre8rZjLNft7HoupGiyxu3MNftR577ZYu8bHe2kK7g

For more information, see the Neon EVM docs.

Author Information

This role was originally developed by Triton One. Patches, suggestions and improvements are always welcome.