DashIOT MQTT Broker Connection Guide

Connecting DashIOT to an MQTT broker requires a WebSocket-compatible endpoint. Because web browsers execute JavaScript inside a sandboxed environment, standard TCP sockets (tcp://...:1883) cannot be opened directly. Instead, browsers establish connections using the WebSocket protocol (ws:// or encrypted wss://).

---

WebSocket URL Schema

When entering the broker URL in DashIOT, use the following schema:

wss://<broker-domain-or-ip>:<port>/<optional-path>

Protocol	Typical Port	Encryption	Recommendation
wss://	8084, 8083, 443	TLS Encrypted	Recommended for public and cloud brokers
ws://	9001, 8080	Unencrypted	Suitable for local network / private test lab

Browser Security Note: If DashIOT is accessed over HTTPS (as in production), browsers enforce mixed-content restrictions. In this case, you must connect using wss:// (secure WebSockets).

---

Free & Public Testing Brokers

For rapid prototyping and bench testing, the following public MQTT brokers support WebSockets:

1. EMQX Public Broker

• WebSocket URL: wss://broker.emqx.io:8084/mqtt
• Protocol: MQTT v3.1.1 / v5.0
• Authentication: None required for public test topics.
• Notes: High availability, global server network. Avoid publishing sensitive data on public topics.

2. HiveMQ Public Broker

• WebSocket URL: wss://broker.hivemq.com:8884/mqtt
• Protocol: MQTT v3.1.1
• Authentication: None required.
• Port: 8884 (WebSocket with SSL).

3. Eclipse Mosquitto

• WebSocket URL: wss://test.mosquitto.org:8081/mqtt
• Protocol: MQTT v3.1.1
• Port: 8081 (Encrypted WebSockets).

---

Self-Hosted MQTT Brokers

If you are running your own local or cloud MQTT infrastructure (such as Eclipse Mosquitto, EMQX, or VerneMQ), you must configure a WebSocket listener.

Configuring Eclipse Mosquitto

In your mosquitto.conf configuration file, add a WebSocket listener block:

# Standard MQTT TCP Listener (Hardware / Gateways)
listener 1883
protocol mqtt

# WebSocket Listener (Browser / DashIOT)
listener 9001
protocol websockets
allow_anonymous true

After updating mosquitto.conf, restart the Mosquitto service:

sudo systemctl restart mosquitto

Then connect DashIOT to:

ws://localhost:9001/

(or wss:// via an Nginx reverse proxy with SSL termination).

---

Troubleshooting Connection Issues

If DashIOT cannot establish a connection to your broker:

1. Mixed Content Block: Verify your broker URL uses wss:// if the host page is served over HTTPS.
2. Firewall / Port Forwarding: Ensure port 9001 or 8084 is allowed through your firewall.
3. CORS & Path: Some brokers require a trailing path, e.g. /mqtt.
4. WebSocket Headers: Verify reverse proxies (e.g. Nginx, Cloudflare) forward Upgrade and Connection headers properly.