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configmqttmosquitto

Using environment variable in mosquitto configuration file

I am trying to set remote_client ID using a value from the system environment variables instead of hardcoding it in the mosquitto.conf configuration file.

Is it possible to pass it inline when starting mosquitto such as:

mosquitto -remote_clientid $envar

Or can I refer environment variables directly from inside the config file?

remote_clientid $envar
Solution

  • I have not tested this, but you can run mosquitto with -c CONFIGFILE, so if you don't want to change your actual mosquitto.conf on disk, you should be able to use a "process substitution" to pass a modified copy of your conf file like this in bash:

    mosquitto -c <(sed "s/remote_clientid=.*/remote_clientid=$CONFIGVAR" /etc/mosquitto.conf)

    Note that this is a bash-ism so you need to be using bash shell.