PetClinic Monolith Workshop

Installing the OpenTelemetry Collector

3 min

The Splunk OpenTelemetry Collector is the core component of instrumenting infrastructure and applications. Its role is to collect and send:

Infrastructure metrics (disk, CPU, memory, etc.)
Application Performance Monitoring (APM) traces
Profiling data
Host and application logs

Remove any existing OpenTelemetry Collectors

If you have completed the Splunk IM workshop, please ensure you have deleted the collector running in Kubernetes before continuing. This can be done by running the following command:

helm delete splunk-otel-collector

The EC2 instance may already have an older version of the collector already installed. To uninstall the collector, run the following commands:

curl -sSL https://dl.signalfx.com/splunk-otel-collector.sh > /tmp/splunk-otel-collector.sh
sudo sh /tmp/splunk-otel-collector.sh --uninstall

To ensure your instance is configured correctly, we need to confirm that the required environment variables for this workshop are set correctly. In your terminal run the following command:

. ~/workshop/petclinic/scripts/check_env.sh

In the output check that all the following environment variables are present and have values set. If any are missing, please contact your instructor:

text
ACCESS_TOKEN
REALM
RUM_TOKEN
HEC_TOKEN
HEC_URL
INSTANCE

We can then go ahead and install the Collector. Some additional parameters are passed to the installation script, they are:

--with-instrumentation - This will install the agent from the Splunk distribution of OpenTelemetry Java, which is then loaded automatically when the PetClinic Java application starts up. No configuration is required!
--deployment-environment - Sets the resource attribute deployment.environment to the value passed. This is used to filter views in the UI.
--enable-profiler - Enables the profiler for the Java application. This will generate CPU profiles for the application.
--enable-profiler-memory - Enables the profiler for the Java application. This will generate memory profiles for the application.
--enable-metrics - Enables the exporting of Micrometer metrics
--hec-token - Sets the HEC token for the collector to use
--hec-url - Sets the HEC URL for the collector to use

bash
curl -sSL https://dl.signalfx.com/splunk-otel-collector.sh > /tmp/splunk-otel-collector.sh && \
sudo sh /tmp/splunk-otel-collector.sh --realm $REALM -- $ACCESS_TOKEN --mode agent --without-fluentd --with-instrumentation --deployment-environment $INSTANCE-petclinic --enable-profiler --enable-profiler-memory --enable-metrics --hec-token $HEC_TOKEN --hec-url $HEC_URL

Next, we will patch the collector to expose the hostname of the instance and not the AWS instance ID. This will make it easier to filter data in the UI:

sudo sed -i 's/gcp, ecs, ec2, azure, system/system, gcp, ecs, ec2, azure/g' /etc/otel/collector/agent_config.yaml

Once the agent_config.yaml has been patched, you will need to restart the collector:

sudo systemctl restart splunk-otel-collector

Once the installation is completed, you can navigate to the Hosts with agent installed dashboard to see the data from your host, Dashboards → Hosts with agent installed.

Use the dashboard filter and select host.name and type or select the hostname of your workshop instance (you can get this from the command prompt in your terminal session). Once you see data flowing for your host, we are then ready to get started with the APM component.