Datadog — Installation Guide

Create a Datadog Account

1.Go to datadoghq.com (or the EU site, datadoghq.eu, if data residency requires it — pick the correct one at signup, since accounts aren't portable between them afterward (needs verification — recheck against current source))

2.Sign up for the 14-day free trial (no credit card required at signup)

3.From Organization Settings → API Keys, copy your API Key — this identifies which org an Agent reports to

4.From Organization Settings → Application Keys, create an Application Key — required for API calls that manage resources (Monitors, SLOs), not just report data

Install the Agent — Kubernetes (Helm)

This is the standard production deployment path, matching Overview's Module 01 example:

bash

helm repo add datadog https://helm.datadoghq.com
helm repo update

helm install datadog datadog/datadog \
  --namespace monitoring --create-namespace \
  --set datadog.apiKey=${DD_API_KEY} \
  --set datadog.clusterName=my-cluster \
  --set datadog.logs.enabled=true \
  --set datadog.logs.containerCollectAll=true \
  --set datadog.apm.portEnabled=true \
  --set clusterAgent.enabled=true \
  --set clusterAgent.metricsProvider.enabled=true

# Verify the DaemonSet is running on every node
kubectl get pods -n monitoring -l app=datadog

# Verify the agent inside a specific pod reports healthy
kubectl exec -n monitoring <datadog-agent-pod> -- agent status

Install the Agent — Single Host (Linux)

bash

DD_API_KEY=${DD_API_KEY} DD_SITE="datadoghq.com" bash -c \
  "$(curl -L https://s3.amazonaws.com/dd-agent/scripts/install_script_agent7.sh)"

# Verify
sudo datadog-agent status
sudo datadog-agent health

Install the Agent — Docker

bash

docker run -d --name datadog-agent \
  -e DD_API_KEY=${DD_API_KEY} \
  -e DD_SITE="datadoghq.com" \
  -v /var/run/docker.sock:/var/run/docker.sock:ro \
  -v /proc/:/host/proc/:ro \
  -v /sys/fs/cgroup/:/host/sys/fs/cgroup:ro \
  gcr.io/datadoghq/agent:7

docker exec -it datadog-agent agent status

Verify Everything Works

bash

# 1. Confirm the agent shows up in the Datadog UI
# Infrastructure → Host Map should show the new host/pod within a few minutes

# 2. Confirm log collection (if enabled)
# Logs → Log Explorer should show incoming log lines

# 3. Enable APM on one test service (Kubernetes example)
kubectl patch deployment my-test-service -p \
  '{"spec":{"template":{"metadata":{"labels":{"admission.datadoghq.com/enabled":"true"}}}}}'
kubectl rollout restart deployment my-test-service
# APM → Services should show the instrumented service within a few minutes of traffic

Common Installation Issues

Agent pod stuck in CrashLoopBackOff

bash

kubectl logs -n monitoring <datadog-agent-pod>
# Most common cause: invalid or missing API key in the Helm values/secret

Host shows in Infrastructure List but no logs appear

Confirm datadog.logs.enabled=true AND datadog.logs.containerCollectAll=true are both set — the first enables the log pipeline, the second is what actually tails every container's stdout/stderr without per-container configuration.

APM shows the service but zero traces

This is the exact scenario walked through in Overview's Interview Prep — check that the auto-instrumentation wrapper (ddtrace-run, or require('dd-trace').init() as the very first line) is actually present in the running process, not just that the Agent itself is healthy. A healthy Agent and flowing host metrics do not guarantee APM instrumentation is active.

Cluster Agent metrics provider not working for HPA

bash

kubectl get pods -n monitoring -l app=datadog-cluster-agent
# Confirm clusterAgent.metricsProvider.enabled=true was set at install time —
# this is a separate flag from basic cluster-agent enablement

What's Installed

After a successful Kubernetes installation:

•Datadog Agent — DaemonSet running on every node, collecting host/container metrics and logs

•Cluster Agent — cluster-level metadata aggregation and (if enabled) the external metrics API for HPA

•APM trace collection — enabled per-pod via the admission-controller label, not cluster-wide by default

Next Steps

Go to the Fundamentals section to run your first metric queries and build a dashboard.