def METHOD_NAME(self):
    # restart the collectd mapper to use recently set port
    c8y_mapper_status = self.startProcess(
        command=self.sudo,
        arguments=["systemctl", "restart", "tedge-mapper-collectd.service"],
        stdouterr="collectd_mapper_restart",
    )
    # check the status of the collectd mapper
    c8y_mapper_status = self.startProcess(
        command=self.sudo,
        arguments=["systemctl", "status", "tedge-mapper-collectd.service"],
        stdouterr="collectd_mapper_status",
    )
    self.assertGrep(
        "collectd_mapper_status.out",
        " MQTT connection error: I/O: Connection refused (os error 111)",
        contains=False,
    )