EMQX | Apporo

EMQX

An MQTT broker for everything in the house that speaks to everything else

Lock it down, then learn to read the log

Lock it down, then learn to read the log

Your broker now carries the MQTT messages for the whole house, which is exactly what makes it one of the doors an attacker most wants to try. This last part of the series does two jobs. First it closes the doors: which of the five ports are actually open on your Home Assistant host, why an EMQX with no authenticator lets every client connect, and how rate limits, TLS and a protected admin surface

Sep 9, 2026

Reading the log, reaching it from outside, and getting it back

Reading the log, reaching it from outside, and getting it back

The Dashboard tells you that something is wrong. It rarely tells you why. This part covers the three things you reach for when the pretty pages run out: the log, Log Trace and the REST API, which between them answer “why was this one client rejected” — in the Dashboard, or from a script with no browser open at all; the built-in ngrok tunnel, which puts port 1883 on the public internet and comes wi

Sep 9, 2026

Nothing is coming through, and the four records that say why

Nothing is coming through, and the four records that say why

The most common complaint in a smart home is a device that is “set up correctly” and still receives nothing. MQTT gives you nothing to look at — no cable to wiggle, no light to check — so the temptation is to start changing things at random. You do not have to. EMQX writes down who connected, what they subscribed to, what it kept, and which setting actually won. This part turns those four records

Sep 9, 2026

Messages from somebody else's broker, and Home Assistant on yours

Messages from somebody else's broker, and Home Assistant on yours

Part 5 was about getting data out of EMQX — a rule fires, an action runs, a connector carries the result somewhere else. This part goes the other way. A Source is the entry point that brings messages from an external MQTT broker back into your own EMQX, and a Republish action puts them onto a local topic your own clients can actually read. Then comes the reason most people wanted this in the first

Sep 9, 2026

Rules, actions and the wire out to everything else

Rules, actions and the wire out to everything else

Up to here EMQX has been a very careful post office: a message goes in on one topic and comes out to whoever subscribed to it, unchanged. The Rule Engine is the point where that stops being true. You write a few lines of SQL, and the broker starts reading the messages passing through it — picking fields out of them, filtering on a condition, renaming things, and then doing something: publishing th

Sep 9, 2026

Getting in is not the same as being allowed

Getting in is not the same as being allowed

Part 3 finished with a client that connects: it has a username, it has a password, and EMQX says yes at the door. That yes answers exactly one question — may you connect. It says nothing about which topics the client may read, which it may write to, or whether anything it sends can be read by whoever else is on the network. This part closes both gaps. Authorization rules pin each account down to t

Sep 9, 2026

Send your first message, then decide who else may

Send your first message, then decide who else may

Part 2 left you with a Dashboard you can read and a publish/subscribe model that has only ever existed on paper. This part closes both gaps in one sitting. First you send a real MQTT message and watch it come back, using a client that is already inside EMQX — nothing to install and not one line of code. Then you deal with what that first message quietly exposed: until you create an authenticator,

Sep 9, 2026

The Dashboard in front of you, and the five words underneath it

The Dashboard in front of you, and the five words underneath it

EMQX is installed and it is running. This part does the two things that make every later part shorter. First, a walk around the Dashboard — what each sidebar group is for, what the front page is actually counting, and where the version number hides — so that when a later part says “go to Access Control,” you already know where that is. Second, the mental model underneath the interface: topic, QoS,

Sep 9, 2026

Mosquitto works, right up until you want to see inside it

Mosquitto works, right up until you want to see inside it

The Mosquitto add-on built into Home Assistant is most people's first MQTT broker, and for a handful of devices it is entirely fine. Push dozens of sensors, switches and telemetry feeds through it and something starts to itch: there is no screen that tells you who is online, who is subscribed, or whether a message ever went out. This part covers what a broker actually does, what EMQX adds on top o

Sep 9, 2026