Troubleshooting Guide

This guide helps you diagnose and resolve common issues with FlowMQ.

Common Issues

Connection Problems

Cannot Connect to Broker

• Check if the broker is running
• Verify correct host and port
• Ensure firewall allows connection
• Validate credentials
• Check SSL/TLS configuration

Connection Drops Frequently

• Check network stability
• Verify keepalive settings
• Monitor system resources
• Check client limits

Message Delivery Issues

Messages Not Received

• Verify topic subscription
• Check QoS levels
• Validate client ID
• Review access control rules

Duplicate Messages

• Check QoS settings
• Verify client clean session flag
• Review client reconnection logic

Performance Issues

High Latency

• Monitor system resources
• Check network conditions
• Review message sizes
• Optimize client configurations

Memory Usage

• Monitor heap usage
• Check message retention
• Review queue limits
• Optimize client connections

Diagnostic Tools

Log Analysis

# Enable debug logging
flowmq --debug

# View logs
tail -f /var/log/flowmq/broker.log

Connection Testing

# Test MQTT connection
mosquitto_sub -h localhost -p 1883 -t test

# Test WebSocket
wscat -c ws://localhost:8080

Performance Monitoring

# Monitor system metrics
flowmq stats

# Check client connections
flowmq clients list

Error Codes

Common Error Codes

• 1: Authentication failure
• 2: Authorization failure
• 3: Connection limit reached
• 4: Invalid protocol
• 5: System resource exhausted

Getting Help

If you can't resolve an issue:

• Check our documentation
• Search release notes for known issues
• Contact support at support@flowmq.io
• Join our community forum