Using Your Node

Besides contributing to decentralization, your Ethereum on ARM node can be used to send transactions and query the Ethereum API.

If this is your first time configuring network access, review Node Security before exposing your node publicly.

Pre-installed Nginx proxy

All recent Ethereum on ARM images include an Nginx reverse proxy preconfigured to route HTTPS (port 443) to the local Execution Layer JSON-RPC port 8545.

This proxy makes wallet and dApp integration straightforward while keeping the internal RPC service bound to 127.0.0.1.

To verify that Nginx and the proxy extras are installed:

sudo apt-get update
sudo apt-get install nginx
sudo apt-get install ethereumonarm-nginx-proxy-extras
sudo systemctl status nginx

The configuration file is located at:

/etc/nginx/sites-available/ethereum-ssl.conf

If you have a valid certificate (Let’s Encrypt or your own CA), edit this file and set the correct certificate paths:

ssl_certificate     /etc/letsencrypt/live/<your-domain>/fullchain.pem;
ssl_certificate_key /etc/letsencrypt/live/<your-domain>/privkey.pem;

Reload Nginx to apply changes:

sudo systemctl reload nginx

Firewall integration

UFW profiles make enabling HTTPS and node networking simple. These profiles are pre-installed on all Ethereum on ARM images (via the ethereumonarm-monitoring-extras package).

Typical configuration:

sudo ufw allow "OpenSSH"
sudo ufw allow "Nginx HTTPS"
sudo ufw allow "Ethereum EL P2P"
sudo ufw allow "Ethereum CL P2P"
sudo ufw enable

Verify that the rules are active:

sudo ufw status verbose
sudo ss -tuln | grep -E "30303|9000|443|8545"

Connecting MetaMask

  1. Open the MetaMask extension and click the network selector (it likely shows “Ethereum Mainnet”).

  2. Click “Add Network”, then select “Add a network manually.”

  3. Enter your node details:

    • Network Name: My Ethereum Node

    • New RPC URL: https://<your-node-domain>

    • Chain ID: 1 (for Mainnet)

    • Currency Symbol: ETH

  4. Save and connect. MetaMask will now route all transactions securely through your node’s HTTPS endpoint.

../_images/metamask-node.jpg

Querying the blockchain

You can query your node directly using curl or any JSON-RPC library.

Example — get the latest block number (replace $YOUR_NODE_IP or domain):

curl --data '{"method":"eth_blockNumber","params":[],"id":1,"jsonrpc":"2.0"}' \
     -H "Content-Type: application/json" \
     -X POST https://$YOUR_NODE_IP

Expected output:

{"jsonrpc":"2.0","id":1,"result":"0x123456"}

  • Ensure Nginx is running and listening on 443.

  • Check that UFW includes “Nginx HTTPS”.

  • Confirm certificate paths in /etc/nginx/sites-available/ethereum-ssl.conf.

Next steps

For information about security, SSH access, and all available firewall profiles, refer back to: Node Security