1. Download and install

1.1. Download address

https://mosquitto.org/download/
version: mosquitto-1.6.9

1.2. Installation

1.2.1. Binary installation

Quick installation (higher versions support snap mode, a quick way to solve dependency package problems)
snap install mosquitto

1.2.2. Windows version binary installation

1.2.2.1. Download and installation

mosquitto-1.6.8-install-windows-x64.exe (~1.4 MB) (64-bit build, Windows Vista and up, built with Visual Studio Community 2017)
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1.2.2.2. Configure environment variables

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1.2.2.3. Start the server

Switch to the installation directory D:\Program Files\mosquitto, and run
mosquitto -c mosquitto.conf

1.2.2.4. Subscription

mosquitto_sub -v -t {topic}

1.2.2.5. Release

mosquitto_pub -t {topic} -m {message}

1.2.3.Ubuntu compile and install

Dependent library installation
Install ssl dependency package
$ sudo apt-get install libssl-dev

mosquitto-1.6.9.tar.gz (319kB) (GPG signature)
Unzip
$ tar zxvf mosquitto-1.6.9.tar.gz
$ cd mosquitto -1.6.9
$ make
$ sudo make install
Start the service
$ mosquitto -v
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2. Basic use of Ubuntu command line (QoS0)

2.1. Start the server

$mosquitto -v

2.2. A client A subscribes

mosquitto_sub -v -t aloha
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2.3. A client B release

mosquitto_pub -t aloha -m hello After
client B connects to the server, it publishes a topic message and disconnects; the
server forwards it to client A;
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