Verify APM SSI on Linux
Before doing anything else: Fully resolve all variables in
## Context to resolve before acting. Do not begin Step 1 until every variable has a concrete value.
Triggers
Invoke this skill when the user expresses intent to:
- Confirm SSI is working after installing the Datadog Agent on Linux
- Check whether a Linux process is being instrumented
- Verify the tracer is running and reporting telemetry
Do NOT invoke this skill if:
- SSI has not been enabled yet — run
agent-installfirst - Services have not been restarted since the agent was installed — restart them first, then verify
Prerequisites
-
agent-installis complete - Application services have been restarted since the agent was installed
pup-cli: check, install, and authenticate
Claude runs
bashpup --version
If not found:
Claude runs
bashbrew tap datadog-labs/pack brew install pup
Check auth:
bashpup auth status --site <DD_SITE>
If not authenticated:
Claude runs
bashpup auth login --site <DD_SITE>
This opens a browser tab for OAuth. Complete the login there — Claude will continue once the command exits.
If valid token — proceed.
ERROR: No browser available: export DD_APP_KEY=<your-app-key>
Context to resolve before acting
| Variable | How to resolve |
|---|---|
DD_HOSTNAME | Hostname as Datadog sees it — from sudo datadog-agent status output |
SERVICE_NAME | Expected service name in APM — ask the user |
ENV | Environment tag — ask the user |
DD_SITE | grep "^site:" /etc/datadog-agent/datadog.yaml via SSH, or ask the user |
SSH_KEY | Path to SSH private key |
SSH_USER | SSH username |
SSH_HOST | Hostname or IP of the target host |
Step 1: Confirm the Process is Injected
Use /proc/<pid>/maps — this is the authoritative check. It shows the actual shared libraries loaded into the running process, which is the only way to confirm the launcher and tracer .so files were actually loaded.
Claude runs
bashssh -o StrictHostKeyChecking=no -i <SSH_KEY> <SSH_USER>@<SSH_HOST> \ "pgrep -a -f '<SERVICE_NAME>' | head -5"
Use the PID from above:
bashssh -o StrictHostKeyChecking=no -i <SSH_KEY> <SSH_USER>@<SSH_HOST> \ "sudo cat /proc/<PID>/maps | grep -E 'launcher|apm-library|datadog'"
If the output includes both the launcher (e.g. launcher.preload.so) and a language library (e.g. apm-library-python) — injection succeeded for this process.
ERROR: Launcher present but no language library — launcher ran but couldn't inject. Check for injection errors:
Claude runs
bashpup apm troubleshooting list --hostname <DD_HOSTNAME> --timeframe 1h
ERROR: Neither present — process was not injected. Check /etc/ld.so.preload:
bashssh -o StrictHostKeyChecking=no -i <SSH_KEY> <SSH_USER>@<SSH_HOST> "cat /etc/ld.so.preload"
If empty — install did not set up the launcher. Re-run the install script with DD_APM_INSTRUMENTATION_ENABLED=host. If non-empty but the process still isn't injected — the process was started before the launcher was installed. Restart the service and recheck.
Step 2: Confirm the Agent is Receiving Traces
Claude runs
bashssh -o StrictHostKeyChecking=no -i <SSH_KEY> <SSH_USER>@<SSH_HOST> \ "sudo datadog-agent status 2>&1 | grep -A 15 'APM Agent'"
Healthy output shows:
feature_auto_instrumentation_enabled: trueReceiver (previous minute)with> 0traces
ERROR: feature_auto_instrumentation_enabled: false — SSI not active on the agent. Check apm_config in /etc/datadog-agent/datadog.yaml.
ERROR: Receiver (previous minute): 0 — agent running but no traces yet. Generate traffic first (see Step 3), then recheck.
Step 3: Confirm the Service is Visible in Datadog
Claude runs
bashDD_SITE=<DD_SITE> pup apm services list --env <ENV> --from 1h
If <SERVICE_NAME> appears with isTraced: true — traces are reaching the Datadog backend.
Flask / ddtrace v3 naming note: With ddtrace >=3.x, Flask spans are emitted as
service:flaskrather thanservice:<DD_SERVICE>. TheDD_SERVICEvalue appears asbase_serviceon the spans. If you setDD_SERVICE=my-app, search forservice:flaskin the APM UI — the service list will showflask, notmy-app. Check thebase_servicetag to confirm it matches yourDD_SERVICE.
ERROR: Service missing — generate traffic to trigger trace creation:
Claude runs
bashssh -o StrictHostKeyChecking=no -i <SSH_KEY> <SSH_USER>@<SSH_HOST> \ "sudo ss -tlnp 2>/dev/null | grep <PID> || sudo netstat -tlnp 2>/dev/null | grep <PID>"
Use the port from above:
bashssh -o StrictHostKeyChecking=no -i <SSH_KEY> <SSH_USER>@<SSH_HOST> \ "for i in \$(seq 1 10); do curl -s -o /dev/null http://localhost:<PORT>/; done"
Wait 30 seconds, then retry:
bashDD_SITE=<DD_SITE> pup apm services list --env <ENV> --from 10m DD_SITE=<DD_SITE> pup traces search --query "service:<SERVICE_NAME>" --from 10m --limit 5
ERROR: Still missing — check for injection errors and go to troubleshoot-ssi:
bashpup apm troubleshooting list --hostname <DD_HOSTNAME> --timeframe 1h
Done
Exit when ALL of the following are true:
- Step 1: launcher + language library both visible in
/proc/<PID>/maps - Step 2: agent APM receiver shows
> 0traces/min - Step 3: service appears in
pup apm services list
If any check fails, go to troubleshoot-ssi.
When all steps pass, automatically proceed to onboarding-summary now — do not ask the user for permission.
Security constraints
- Never write a raw API key into any file or chat message
- Always confirm before restarting production services

