.. _using-your-node:

.. meta::
   :description lang=en: Use your Ethereum node RPC on ARM. Connect MetaMask, query blockchain data, and configure Nginx reverse proxy for secure HTTPS access.
   :keywords: Ethereum RPC access, MetaMask own node, JSON-RPC query, Nginx Ethereum, private Ethereum node

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
:doc:`../system/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:

.. prompt:: bash $

   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:

.. code-block:: nginx

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

Reload Nginx to apply changes:

.. prompt:: bash $

   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:

.. prompt:: bash $

   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:

.. prompt:: bash $

   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.

.. figure:: /_static/images/metamask-node.jpg
   :figwidth: 600px
   :align: center


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):

.. prompt:: bash $

   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:
:doc:`../system/security`