services.prometheus.exporters.snmp.environmentFile

EnvironmentFile as defined in systemd.exec(5).

Secrets may be passed to the service without adding them to the world-readable Nix store, by specifying placeholder variables as the option value in Nix and setting these variables accordingly in the environment file.

Environment variables from this file will be interpolated into the config file using envsubst with this syntax: $ENVIRONMENT ${VARIABLE}

For variables to use see Prometheus Configuration.

If the file path is set to this option, the parameter --config.expand-environment-variables is implicitly added to ExecStart.

Note that this file needs to be available on the host on which this exporter is running.