How to show Raspberry Pi temperatures in your Datadog dashboard

So, I’ve set up a cluster of 4 Raspberry Pis to learn and experiment with distributed systems.

I also wanted to track various metrics while running the cluster, so I set up Datadog APMs on all of them and since the pis usually run hot, I wanted to track their temperatures for warning signs. Here is how you can send your temperature info to Datadog.

Create 2 files, a temp.yaml and a temp.py (the names should match).

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# /etc/datadog-agent/conf.d/temp.yaml
instances: [{}]
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# /etc/datadog-agent/checks.d/temp.py

from pathlib import Path

# the following try/except block will make the custom check compatible with any Agent version
try:
    # first, try to import the base class from new versions of the Agent...
    from datadog_checks.base import AgentCheck
except ImportError:
    # ...if the above failed, the check is running in Agent version < 6.6.0
    from checks import AgentCheck

# content of the special variable __version__ will be shown in the Agent status page
__version__ = "1.0.0"

class TempCheck(AgentCheck):
    def check(self, instance):
        self.gauge(
            "custom.temperature",
            (int(Path("/sys/class/thermal/thermal_zone0/temp").read_text().strip()) / 1000),
            tags=[],
        )

The meat of this code is the following, where we send a guage metric named custom.temperature and send it the temperature by reading /sys/class/thermal/thermal_zone0/temp (this is how you can read the temperature for a pi with ubuntu installed, you may have to tweak this bit for other distros) 

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self.gauge(
    "custom.temperature",
    (int(Path("/sys/class/thermal/thermal_zone0/temp").read_text().strip()) / 1000),
    tags=[],
)

That’s it, you can tack other metrics in their too if you’d like to. You’ll also need to restart your datadog agent for it to start sending these metrics.

You can read more about custom metrics in Datadog here

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