EMQ - Erlang MQTT Broker
Erlang Makefile
Latest commit 153ed22 Jan 17, 2017 @emqplus emqplus committed on GitHub Merge pull request #868 from emqtt/emq20
Merge PR #864 from grutabow


EMQ - Erlang MQTT Broker Build Status

EMQ (Erlang MQTT Broker) is a distributed, massively scalable, highly extensible MQTT message broker written in Erlang/OTP.

EMQ is fully open source and licensed under the Apache Version 2.0. EMQ implements both MQTT V3.1 and V3.1.1 protocol specifications, and supports MQTT-SN, CoAP, WebSocket, STOMP and SockJS at the same time.

EMQ provides a scalable, reliable, enterprise-grade MQTT message Hub for IoT, M2M, Smart Hardware and Mobile Messaging Applications.

The 1.0 release of the EMQ broker has scaled to 1.3 million concurrent MQTT connections on a 12 Core, 32G CentOS server.

Please visit emqtt.io for more service. Follow us on Twitter: @emqtt


  • Full MQTT V3.1/V3.1.1 support
  • QoS0, QoS1, QoS2 Publish/Subscribe
  • Session Management and Offline Messages
  • Retained Message
  • Last Will Message
  • TCP/SSL Connection
  • MQTT Over WebSocket(SSL)
  • HTTP Publish API
  • MQTT-SN Protocol
  • STOMP protocol
  • STOMP over SockJS
  • $SYS/# Topics
  • ClientID Authentication
  • IpAddress Authentication
  • Username and Password Authentication
  • Access control based on IpAddress, ClientID, Username
  • LDAP Authentication/ACL
  • HTTP Authentication/ACL
  • MySQL Authentication/ACL
  • Redis Authentication/ACL
  • PostgreSQL Authentication/ACL
  • MongoDB Authentication/ACL
  • Cluster brokers on several nodes
  • Bridge brokers locally or remotely
  • mosquitto, RSMB bridge
  • Extensible architecture with Hooks and Plugins
  • Passed eclipse paho interoperability tests
  • Local Subscription
  • Shared Subscription


The EMQ broker is cross-platform, which can be deployed on Linux, Unix, Mac, Windows and even Raspberry Pi.

Download the binary package for your platform from http://emqtt.io/downloads.

Documentation on emqtt.io/docs/v2/, docs.emqtt.com for installation and configuration guide.

Build From Source

The EMQ broker requires Erlang/OTP R18+ to build.

git clone https://github.com/emqtt/emq-relx.git

cd emq-relx && make

cd _rel/emqttd && ./bin/emqttd console


The EMQ broker is highly extensible, with many hooks and plugins for customizing the authentication/ACL and integrating with other systems:

Plugin Description
emq_plugin_template Plugin template and demo
emq_dashboard Web Dashboard
emq_auth_username Username/Password Authentication Plugin
emq_auth_clientid ClientId Authentication Plugin
emq_auth_mysql MySQL Authentication/ACL Plugin
emq_auth_pgsql PostgreSQL Authentication/ACL Plugin
emq_auth_redis Redis Authentication/ACL Plugin
emq_auth_mongo MongoDB Authentication/ACL Plugin
emq_auth_http Authentication/ACL by HTTP API
emq_auth_ldap LDAP Authentication Plugin
emq_mod_presence Presence Module
emq_mod_rewrite Rewrite Module
emq_mod_retainer Store MQTT Retained Messages
emq_mod_subscription Subscribe topics when client connected
emq_sn MQTT-SN Protocol Plugin
emq_coap CoAP Protocol Plugin
emq_stomp Stomp Protocol Plugin
emq_recon Recon Plugin
emq_reloader Reloader Plugin
emq_sockjs SockJS(Stomp) Plugin



QingCloud is the world’s first IaaS provider that can deliver any number of IT resources in seconds and adopts a second-based billing system. QingCloud is committed to providing a reliable, secure, on-demand and real-time IT resource platform with excellent performance, which includes all components of a complete IT infrastructure system: computing, storage, networking and security.

The q.emqtt.com hosts a public Four-Node EMQ cluster on QingCloud:



Apache License Version 2.0