Mosquitto is an open source implementation of a server for version 5.0, 3.1.1, and 3.1 of the MQTT protocol. It also includes a C and C++ client library, and the mosquitto_pub and mosquitto_sub utilities for publishing and subscribing.
See the following links for more information on MQTT:
MQTT v3.1.1 standard: https://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html
MQTT v5.0 standard: https://docs.oasis-open.org/mqtt/mqtt/v5.0/mqtt-v5.0.html
Mosquitto project information is available at the following locations:
Main homepage: https://mosquitto.org/
Find existing bugs or submit a new bug: https://github.com/eclipse/mosquitto/issues
Source code repository: https://github.com/eclipse/mosquitto
There is also a public test server available at https://test.mosquitto.org/
Documentation for the broker, clients and client library API can be found in the man pages, which are available online at https://mosquitto.org/man/. There are also pages with an introduction to the features of MQTT, the mosquitto_passwd utility for dealing with username/passwords, and a description of the configuration file options available for the broker.
Detailed client library API documentation can be found at https://mosquitto.org/api/
—- QPKG INTEGRATION —
on start create a “mosquitto” user cannot be run as root/admin
all config file : /opt/Mosquitto81/etc/mosquitto.conf
start automatically mosquiito pointing this config file
all mosquitto command lines are added to NAS $PATH