Mosquitto MQTT Broker
About
Eclipse Mosquitto™ is an open source (EPL/EDL licensed) message broker that implements the MQTT protocol versions 3.1 and 3.1.1. MQTT provides a lightweight method of carrying out messaging using a publish/subscribe model. This makes it suitable for "Internet of Things" messaging such as with low power sensors or mobile devices such as phones, embedded computers or microcontrollers like the Arduino.
This description is about how to install the mosquitto broker service on SME9/Centos6.
Installation
Setting the Mosquitto MQTT YUM repositories
/sbin/e-smith/db yum_repositories set mosquitto repository \ Name 'Mosquitto MQTT CentOS-$releasever' \ BaseURL 'http://download.opensuse.org/repositories/home:/oojah:/mqtt/CentOS_CentOS-$releasever/' \ EnableGroups no \ GPGCheck yes \ GPGKey 'http://download.opensuse.org/repositories/home:/oojah:/mqtt/CentOS_CentOS-$releasever//repodata/repomd.xml.key' \ Visible no \ status disabled
signal-event yum-modify
Yum Installation
yum install mosquitto mosquitto-clients --enablerepo=mosquitto
Create a 'mosquitto' user
adduser mosquitto
Set SME Configuration
config set mosquitto service config setprop mosquitto TCPPort 1883 config setprop mosquitto access public config show mosquitto signal-event remoteaccess-update
Set custom template for /etc/hosts.allow
mkdir /etc/e-smith/templates-custom/etc/hosts.allow cd /etc/e-smith/templates-custom/etc/hosts.allow touch mosquitto
Edit the file 'mosquitto' to have the following content:
{
$DB->hosts_allow_spec('mosquitto');
}
and expand the template:
expand-template /etc/hosts.allow
Enable As Service
chkconfig mosquitto --add chkconfig mosquitto --level 2345 on
cd /etc/rc.d/rc7.d ln -s ../init.d/mosquitto S50mosquitto
Setup Log Path
mkdir /var/log/mosquitto
Enable Write Access To Log
cd /var/log/mosquitto chmod mosquitto:mosquitto .
Update Mosquitto Configuration
In /etc/mosquitto/mosquitto.conf
Add line:
user mosquitto
Add/change line:
log_dest file /var/log/mosquitto/mosquitto.log
Start Mosquitto Service
service mosquitto start
Enable Port 1883 Forwarding
On your internet gateway router, enable TCP port 1883 to allow MQTT clients access the broker.
Testing Access To The Broker
On a command line on your server use something like:
mosquitto_pub -d -t sensors/temperature -m 32 -q 1
If you get an output like below, your server is functional:
Client mosqpub/22329-franka sending CONNECT Client mosqpub/22329-franka received CONNACK Client mosqpub/22329-franka sending PUBLISH (d0, q1, r0, m1, 'sensors/temperature', ... (2 bytes)) Client mosqpub/22329-franka received PUBACK (Mid: 1) Client mosqpub/22329-franka sending DISCONNECT