ERR_NGROK_8012
Message
Traffic was successfully tunneled to the ngrok agent, but the agent failed to establish a connection to the upstream web service at ADDR
.
Overview
This error occurs when the ngrok agent successfully receives traffic but fails to establish a connection with your local service (the "upstream" service). While the tunnel is created successfully, ngrok cannot forward the traffic to your application.
Common Issues and Solutions
-
Local Service Not Running or Inaccessible
Cause: The web service or application on your local machine is not active or cannot be reached.
Resolution:
- Start your local service.
- Confirm you can access it directly (e.g., http://localhost:8080).
- Restart ngrok with the correct port number.
-
Incorrect Port Specified
Cause: The port in your ngrok command doesn't match your local service's port.
Resolution:
- Verify the port your local service is using.
- Update your ngrok command to use the correct port.
- Example: Use
ngrok http 3000
if your service runs on port 3000.
General Troubleshooting Steps
- Verify local service accessibility without ngrok.
- Ensure the latest ngrok version is installed.
- Restart the ngrok agent.
Further help
If you're having trouble resolving this error, please reach out to support@ngrok.com