Directory

Directory

The directory structure of EMQ X Broker obtained by different installation methods will be different:

Description	ZIP	Binary	Homebrew (MacOS)
Executable file directory	`./bin`	`/usr/lib/emqx/bin`	`/usr/local/bin`
Data files	`./data`	`/var/lib/emqx/data`	`/usr/local/Cellar/emqx//data`
Erlang Virtual machine files	`./erts-`	`/usr/lib/emqx/erts-`	`/usr/local/Cellar/emqx//erts-`
Configuration file directory	`./etc`	`/etc/emqx/etc`	`/usr/local/Cellar/emqx//etc`
Dependency directory	`./lib`	`/usr/lib/emqx/lib`	`/usr/local/Cellar/emqx//lib`
Log file	`./log`	`/var/log/emqx`	`/usr/local/Cellar/emqx//log`
Start related scripts and schema files	`./releases`	`/usr/lib/emqx/releases`	`/usr/local/Cellar/emqx//releases`

In the above directories, bin, etc, data andlog are commonly used by users.

bin directory

emqx、emqx.cmd

The executable file of EMQ X Broker can be found in Basic Command.

emqx_ctl、emqx_ctl.cmd

The executable file of EMQ X Broker management command, you can check Management Command CLI for specific use.

etc directory

EMQ X Broker is set by configuration files in the etc directory. The main configuration files include:

Configuration file	Description
emqx.conf	EMQ X Broker configuration file
acl.conf	EMQ X Broker default ACL rule configuration file
plugins/*.conf	EMQ X Broker various plug-in configuration files
certs	EMQ X Broker SSL certificate file

The specific configuration content of EMQ X Broker can be viewed in Configuration Item.

data directory

EMQ X Broker stores the running data in the data directory. The main files include:

configs/app.*.config

EMQ X Broker reads the configuration in etc/emqx.conf and etc/plugins/*.conf, converts it to the Erlang native configuration file format, and reads the configuration at runtime.

loaded_plugins

The loaded_plugins file records the list of plug-ins that was started by EMQ X Broker by default. You can modify this file to add or delete plug-ins. The startup item format in loaded_plugins is {<Plugin Name>, <Enabled>}., the <Enabled>field is a Boolean type, and EMQ X Broker will determine whether to start this plugin according to the value of <Enabled>. For more information about plugins, please see plug-ins.

$ cat loaded_plugins
{emqx_management,true}.
{emqx_recon,true}.
{emqx_retainer,true}.
{emqx_dashboard,true}.
{emqx_rule_engine,true}.
{emqx_bridge_mqtt,false}.

mnesia

Mnesia database is a distributed DBMS in Erlang, which can directly store various data structures of Erlang.

EMQ X Broker uses the Mnesia database to store its own running data, such as alarm records, resources and rules created by the rule engine, Dashbaord user information, etc. These data will be stored under the mnesia directory. Once the directory is deleted, EMQ X Broker will lose all business data.

You can query the system information of the Mnesia database in EMQ X Broker through the emqx_ctl mnesia command. For details, please see Management Command CLI.

log directory

emqx.log.*

For the log file generated when EMQ X Broker is running, please check Log and Trace.

crash.dump

The crash dump file of EMQ X Broker can be modified through etc/emqx.conf , and the specific content can be viewed in configuration item.

erlang.log.*

It can control the copy of the console log when EMQ X Broker is started in the background with emqx start.