🤖 n8n + Telegram Bot Integration with ngrok (Self-Hosted on Ubuntu VM)

This project documents how I set up n8n, an open-source workflow automation tool, to work with a Telegram bot using ngrok for public webhook access. Everything runs self-hosted inside Docker containers on an Ubuntu Server VM (hosted in VMware Workstation bridged to LAN) on a Windows 11 Education Edition machine. The key idea is to trigger workflows in n8n based on incoming Telegram messages, even when the setup is entirely behind NAT/firewall, without static IP or HTTPS certs. All traffic is tunneled securely via ngrok.

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📺 YouTube Tutorial

I recorded a full walkthrough of this setup. You can follow along with the video here:
🎬 https://www.youtube.com/watch?v=NmcVa_g9kzc

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🧩 System Architecture

This stack consists of multiple containers:

• n8n: The main automation engine running at port 5678
• ngrok: Exposes n8n’s local port securely over HTTPS
• Portainer: (Optional) Docker management UI
• WatchYourLAN: (Optional) Network scanner

All containers are connected via a custom Docker network called n8n-net. This allows internal DNS resolution, so n8n can refer to http://ollama:11434 or http://ngrok:4040 seamlessly.

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⚙️ Workflow Concept

The setup allows you to:

• Create Telegram-triggered workflows inside n8n
• Filter messages based on chat ID (to isolate group vs private messages)
• Respond with logic, notifications, or integrations (e.g., APIs, emails, AI, etc.)

When a message is sent to your Telegram bot (in a group or private), Telegram sends it to the webhook URL that n8n registers. Since n8n runs locally, the webhook wouldn't normally be reachable — that’s where ngrok comes in, exposing it over a public HTTPS URL.

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🛠️ Installation & Setup

Step 1: Create a Docker Network

This ensures all containers can communicate by name:

docker network create n8n-net

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Step 2: Run ngrok Container

This exposes n8n:5678 to the public via HTTPS. Replace the NGROK_AUTHTOKEN with your token from https://dashboard.ngrok.com:

docker run -d \
  --name ngrok \
  --network n8n-net \
  -p 4040:4040 \
  -e NGROK_AUTHTOKEN=your_ngrok_token \
  ngrok/ngrok http n8n:5678

You can access the ngrok web UI at: 📡 http://localhost:4040

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Step 3: Get Your ngrok Public URL

After the container starts, get the public URL that ngrok assigned:

curl http://localhost:4040/api/tunnels | jq -r '.tunnels[0].public_url'

You’ll get something like:

https://143f02d83119.ngrok-free.app

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Step 4: Run n8n Docker Container

Now that you have the ngrok HTTPS URL, launch n8n with it passed as environment variables:

docker rm -f n8n

docker run -d \
  --name n8n \
  --network n8n-net \
  -p 5678:5678 \
  -v n8n_data:/home/node/.n8n \
  -e N8N_HOST=n8n \
  -e N8N_PORT=5678 \
  -e N8N_PROTOCOL=http \
  -e WEBHOOK_URL=https://143f02d83119.ngrok-free.app \
  -e WEBHOOK_TUNNEL_URL=https://143f02d83119.ngrok-free.app \
  -e N8N_SECURE_COOKIE=false \
  n8nio/n8n

This ensures that n8n uses your ngrok public address when registering webhooks (e.g., with Telegram).

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Step 5: Create Telegram Bot

1. Open Telegram and talk to @BotFather
2. Use /newbot and follow the instructions
3. Copy the bot token shown at the end

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Step 6: Add Bot to Telegram Group

If you want your bot to respond to messages in a private group:

1. Add the bot to the group like any other member
2. Promote it to admin
3. Send a message in the group to generate activity

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Step 7: Find the Group Chat ID

You can find the group chat ID using one of two ways:

• Use the Telegram Trigger node and inspect the incoming message JSON
• Or visit:

https://api.telegram.org/bot<YOUR_BOT_TOKEN>/getUpdates

Look for a line like:

"chat": {
  "id": -1001234567890,
  ...
}

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Step 8: Create the Workflow in n8n

1. Open n8n via https://<your-ngrok-url>

2. Add a Telegram Trigger node

3. Use your bot token in the credentials

4. Add an IF node:

   • Condition: {{$json["message"]["chat"]["id"]}} is equal to -1001234567890

5. Optionally, add a Set node to process or reply

6. Save and activate the workflow

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🧪 Testing

• Click "Execute Node" in the Telegram Trigger
• Send a message in your group
• The workflow should trigger if the chat ID matches
• The message will pass through the IF node and continue the flow

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🛠️ Optional Tools

WatchYourLAN (LAN IP monitoring)

docker run -d \
  --name watchyourlan \
  --network host \
  -e TZ="Asia/Kolkata" \
  -e WEB_USER=admin \
  -e WEB_PASS=pass \
  aceberg/watchyourlan

Portainer (Docker UI)

docker run -d \
  --name portainer \
  -p 9000:9000 \
  -v /var/run/docker.sock:/var/run/docker.sock \
  portainer/portainer-ce

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🧯 Troubleshooting

Telegram Trigger gives HTTPS error?

Make sure WEBHOOK_URL is set to your ngrok HTTPS address, not localhost.

n8n gives "secure cookie" warning?

Set N8N_SECURE_COOKIE=false to avoid cookie problems through the tunnel.

Workflow doesn’t trigger?

Check:

• Bot has admin rights
• Chat ID in IF node is correct
• ngrok tunnel is live
• ngrok URL hasn't changed (it does on restart)

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📌 Notes

• This setup is ideal for quick automation testing or internal bots
• For production use, consider a reverse proxy like Caddy with a domain + TLS
• You can add AI (LLMs like OpenRouter, Ollama) via HTTP nodes for chatbot use cases

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🙋 Author

Built by @flatmarstheory Inspired by self-hosting simplicity, Docker networking, and no-frills automation. 📺 YouTube tutorial: https://www.youtube.com/watch?v=NmcVa_g9kzc

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📄 License

This project is released under the MIT License. Feel free to fork, modify, and contribute.