opentelemetry-helm-charts VS opentelemetry-collector

Refer to the official documentation for the Helm chart for comprehensive instructions and configuration options: OpenTelemetry Helm Charts Documentation.

In my latest Nomadification Project (TM), I got the OpenTelemetry Demo App to run on Nomad (with HashiQube, of course). To do this, I used the OpenTelemetry Demo App Helm Chart as my guide. In doing this, and other Nomadifications, I realized that I’ve never gone through the process of explaining the conversion process from Kubernetes manifests to Nomad jobspecs.

Y’all...I’m so excited, because I finally got to work on an item on my tech bucket list. Last week, I began the process of translating OpenTelemetry (OTel) Demo App’s Helm Charts to HashiCorp Nomad job specs.

After creating a Kubernetes cluster, we needed to create a Kubernetes resource before we could apply the Helm chart to install the OpenTelemetry demo app. The Demo App’s Helm Chart deploys an OpenTelemetry Collector. We wanted to configure the Collector to send OTel data to Lightstep. To do so, you need to add a Lightstep Access Token, which is stored as a Kubernetes secret.

Deploy the OpenTelemetry Demo App using the OpenTelemetry Demo Helm Chart

Now let's dive right in and figure out how to use the Helm chart provided by OpenTelemetry.

But how does one monitor a Collector? The OTel Collector already emits metrics for the purposes of its own monitoring. These can then be sent to your Observability backend for monitoring.

Maybe, you are asking yourself: "But I already had instrumented my applications with vendor-specific libraries and I'm using their agents and monitoring tools, why should I change to OpenTelemetry?". The answer is: maybe you're right and I don't want to encourage you to update the way how you are doing observability in your applications, that's a hard and complex task. But, if you are starting from scratch or you are not happy with your current observability infrastructure, OpenTelemetry is the best choice, independently of the backend telemetry tool that you are using. I would like to invite you to take a look at the number of exporters available in the collector contrib section, if your backend tracing tool is not there, probably it's already using the Open Telemetry Protocol (OTLP) and you will be able to use the core collector. Otherwise, you should consider changing your backend telemetry tool or contributing to the project creating a new exporter.

To receive OTLP data, you set up the standard otlp receiver to receive data in HTTP or gRPC format. To forward traces and metrics, a batch processor was defined to accumulate data and send it every 100 milliseconds. Then set up a connection to Tempo (in otlp/tempo exporter, with a standard top exporter) and to Prometheus (in prometheus exporter, with a control exporter). A debug exporter also was added to log info on container standard I/O and see how the collector is working.

You can find more details on advanced configurations here.

> opentelemetry is basically a house of antipatterns

"Look on My Works Ye Mighty and Despair!"

https://github.com/open-telemetry/opentelemetry-collector/tr... -> https://github.com/open-telemetry/opentelemetry-collector-re... ... and then a reasonable person trying to load that mess into their head may ask 'err, what's the difference between go.opentelemetry.io/collector and github.com/open-telemetry/opentelemetry-collector-contrib?'

  $ curl -fsS go.opentelemetry.io/collector | grep go-import

open-telemetry/opentelemetry-collector: OpenTelemetry Collector (github.com)

There are 2 collector types: the core and the contrib. I have used the contrib as it features the splunk_hec exporter.

We are setting the deployment to have exactly 1 replica and setting the container CPU and memory limits according to the minimum that was checked for performance in their docs.

Lightstep ingests data in native OpenTelemetry Protocol (OTLP) format, so we will use the OTLP Exporter. The exporter can be called either otlp or follow the naming format otlp/. We could call it otlp/bob if we wanted to. We're calling our exporter otlp/ls to signal to us that we are using the OTLP exporter to send the data to Lightstep.

Then, we set up a batch processor that batches up the spans together and every 1 second sends the batch forward. In production, you would want more than 1 second, but I set this here to 1 second for instant feedback in Jaeger.