Newbie: remapping tags and processor pivot

Telegraf
,
1

Hi Folks.
I’m exploring Telegraf to consume some MQTT data from a set of devices living off in the woods. ( long story ). I feel like I am missing some core concepts. anyway specifically here’s what’s up:

I’m starting with a simplest MQTT message ( from MQTT Explorer )

MQTT:Explorer:> arc-km-assistant/sensor/arc_km_cpu_utilization/state

Which has a value of the CPU % utilization. which is fine.

All the MQTT messages from the devices are “flat” → no JSON etc etc.

I’m running telegraf from the command line, passing in my conf. file and just watching the log output. I understand the output in the log is what would be passed on to InfluxDB3.

In my conf file I am remapping the topic message thing via the name_override directive

here is my inputs.mqtt_consumer.topic_parsing block:

[[inputs.mqtt_consumer.topic_parsing]]

# MQTT:Explorer:> arc-km-assistant/sensor/arc_km_cpu_utilization/state

#Traffic no xlation:> topic=arc-km-assistant/sensor/arc_km_memory_utilization/state value=“92.8” 1765857460844249977

  topic = “arc-km-assistant/sensor/arc_km_cpu_utilization/state”

# topic = “+/+/+/+”  # this is a brute which matches all 4 element mqtt messages. used in exploration

# remap topic first position to 'site, second to type, third to cpu to pass along ‘cpu’ for processors.pivot to slide the value into that name

  tags = “site/type/cpu/_”

  [[processors.pivot]]
    tag_key = “cpu”
    value_key = “value”

so what’s confusing me is that this is the output I get:

ARC_Telemetry_Dev,site=arc-km-assistant,type=sensor arc_km_cpu_utilization=20.6 1766087365095091243

I had thought that I was remapping the 3rd position ( arc_km_cpu… ) to cpu, and then using that pivot dealy to move the float value in.

so that I would have cpu=20.8

what have I missed with the tag reassignment and pivot processing?

oh also, is this they proper telegraf way to do this remapping?