Observability and tracing · Lesson 2 of 15 · 5 min

Inspect gateway metrics

Metrics need units, scope and a time window. Counters, rates and gauges should not be compared as though they measured the same thing.

Open the lab Course map

Mastery 0/3Run itExplain itApply it

learner@clairos:~ $

↑ history · Tab complete · Ctrl+C cancel · Esc, Tab to leaveExit 0

Your objectives

Hints are always available. Wrong turns never cost XP.

1
Read the case evidence
Read /opt/ai-lab/cases/aiops-observability-tracing-002.json. Separate the recorded facts from your assumptions.
Hint & worked example
Metrics need units, scope and a time window. Counters, rates and gauges should not be compared as though they measured the same thing.
The complete case JSON is read successfully.
```
cat /opt/ai-lab/cases/aiops-observability-tracing-002.json
```
Common mistake to avoid: Report 2400 requests per second from the counter value alone.
2
Isolate the deciding signal
Select the type field from the case JSON. What does it establish—and what does it not establish?
Hint & worked example
Treat 2400 as a counter observation, not an instantaneous requests-per-second value.
A successful JSON query isolates type.
```
jq .type /opt/ai-lab/cases/aiops-observability-tracing-002.json
```
Common mistake to avoid: Using a different case or an unrelated signal as the justification.
3
Record your operational decision
Choose the justified code: interpret-as-counter, change-without-evidence, or ignore-the-signal. Save that one code followed by a newline in /home/learner/lab/aiops-observability-tracing-002-decision.txt.
Hint & worked example
Treat 2400 as a counter observation, not an instantaneous requests-per-second value.
The decision artifact contains the correct code, not just a matching command in history.
```
printf '%s\n' 'interpret-as-counter' > /home/learner/lab/aiops-observability-tracing-002-decision.txt
```
Common mistake to avoid: Report 2400 requests per second from the counter value alone.

Understand the pattern

Metrics need units, scope and a time window. Counters, rates and gauges should not be compared as though they measured the same thing.

Interpret the evidence

Treat 2400 as a counter observation, not an instantaneous requests-per-second value.

A tempting mistake

Report 2400 requests per second from the counter value alone.

All names, measurements, prices, versions, and thresholds in this exercise are fictional training data. The evidence supports this bounded scenario, not a claim about a live provider.

Worked example and expected result

$ cat /opt/ai-lab/cases/aiops-observability-tracing-002.json

{
  "fixture": "Fictional training data; not a live measurement.",
  "name": "gateway_requests_total",
  "type": "counter",
  "value": 2400,
  "window_seconds": 300
}

Exit status: 0. The command completed successfully in the training fixture.

$ jq .type /opt/ai-lab/cases/aiops-observability-tracing-002.json

"counter"

Exit status: 0. The command completed successfully in the training fixture.

$ printf '%s\n' 'interpret-as-counter' > /home/learner/lab/aiops-observability-tracing-002-decision.txt

(no output; exit 0)

Exit status: 0. The command completed successfully in the training fixture.

Try a variation

Name the assumption that would have to change for “interpret-as-counter” to stop being the justified action. Do not silently replace missing evidence with a guess.

Explain it

What does the evidence in “Inspect gateway metrics” justify?Make the change now and gather the missing evidence afterward.Treat 2400 as a counter observation, not an instantaneous requests-per-second value.Report 2400 requests per second from the counter value alone.

Apply it elsewhere

A colleague concludes: “Report 2400 requests per second from the counter value alone.” What should you do?Reject that conclusion; return to the case evidence and its stated limits.Accept it because the training command completed.Treat this fixture as a live measurement.

Keep the momentum.

Complete the lab, then explain and apply the pattern.

Next: Read latency percentiles Try an incident drill

Anonymous lesson and mastery progress lasts for this session. Sign in to keep synced lesson XP between sessions; mastery stays device-local. No speed bonus, lost lives, or hint penalties.

Keep learning

Case methodology: evidence, limits, decision