Ethereum Connection Refused: A Troubleshooting Guide

When attempting to connect to the Ethereum network using a WebSockets client, such as curl in a container running Ubuntu 16.04, you may encounter an error message indicating that the connection was refused by the Ethereum node. In this article, we will explore the possible reasons behind this error and provide steps to resolve it.

Why is the connection refused?

There are several reasons why the connection might be refused:

• Invalid or incomplete credentials: Ensure that the user and pass variables passed in the --user option contain valid Ethereum wallet addresses.

• Incorrect WebSocket handshake: The Ethereum node may not be configured to listen for incoming connections on the specified port (7687 by default). Verify that the container is running and listening on this port.

• Firewall or network issues: If you’re behind a firewall, it may block the connection. Check your firewall configuration to ensure that the port is allowed.

• Outdated Ethereum node software: Ensure that the Ethereum node software (e.g., ethers.js) is up-to-date.

Troubleshooting steps

• Verify credentials

  :

* Double-check the user and pass variables passed in the --user option to ensure they contain valid Ethereum wallet addresses.

• Check WebSocket handshake:

* Verify that the container is running and listening on port 7687 by running docker ps -f name=bitecoin-ethereum. If not, start it manually using docker run ...

• Firewall or network issues:

* Check your firewall configuration to ensure that port 7687 is allowed.

• Update Ethereum node software:

* Run sudo apt update and install the latest Ethereum node software (e.g., ethers.js) using sudo apt install ethers.js

• Verify network connection:

* Ensure that you can connect to the Ethereum node from another terminal or command prompt.

Example Use Case

Here’s an example of how you can use curl in a container running Ubuntu 16.04 and a web server running Docker:

Create a new user and wallet on Bitcoin Core (BTC)

echo "key = 'your-wallet-address';" > bitcoin.conf



Start the Bitcoin node

sudo systemctl start btcd --no-logfile



Create a new Ethereum wallet address using ethers.js

ethers.js new --wallet-type=eth



Connect to the Ethereum network using curl

curl --user your-username:your-password --data-binary '{"jsonrpc":"1.0","method":"eth_getTransactionCount","params":["0x0000000000000000000000000000000000000001"],"id":1}

By following these steps and troubleshooting potential issues, you should be able to resolve the “Connection Refused” error when using curl in a container running Ubuntu 16.04 and a web server running Docker with Ethereum.