Page 6 of 8~120 min topic

Deploy a RAG app

Instrument deploy versions and request traces

Metrics for ready_ratio == 1 and citation_miss_rate ≤ 0.02 during rollout must distinguish bad input from component failure for platform engineer shipping faq-index@sha256:a1b2 to staging.

~15 min this pageTesting and observability

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Golden signals for this system

Instrument containerized café FAQ RAG with readiness probes and versioned index pin so platform engineer shipping faq-index@sha256:a1b2 to staging can answer: demand, errors, latency/age, saturation. Emit fields needed by ready_ratio == 1 and citation_miss_rate ≤ 0.02 during rollout with bounded labels. Sample successful high-volume traces; keep errors and rollout transitions denser within policy.

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Alert path worth paging

Define at least one alert that would fire for DEPLOY-EMPTY-INDEX-5, with a for/pending window that survives deploy blips. Missing scrape or missing revision labels must not look like health. Include a trace/log example id format you will actually search.

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Implementation artifact

emit("rag_ready", digest=live, matched=live == pinned)
emit("citation_miss_rate", value=misses / max(total, 1))

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Tests for telemetry

Add a unit/integration check that metrics increment on the happy path and on the new pods serve empty index while old pods terminate — citation miss spike branch. Store machine-readable output in CI artifacts when practical.

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Stage depth

Cardinality discipline: tenant and revision are usually enough; raw question text is not a label. Exemplars or trace links beat screenshots alone when debugging DEPLOY-EMPTY-INDEX-5. Define who owns alert fatigue review. If you export to a vendor, record retention and access. Synthetic probes should use non-sensitive fixtures and still exercise GET /readyz. Practice the query you will type at 2am once, while calm.

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Field notes for `deploy-rag-app` / `observability`

Document the exact PromQL or log query in the runbook stub for this service. Verify histograms have buckets around your SLO target. Add a canary synthetic check that exercises the oracle path every few minutes in staging. Confirm that PII redaction happens before export. Track build/version as a label on the golden signals. Delete noisy debug logs before they become accidental product dependencies. In this chapter the product is containerized café FAQ RAG with readiness probes and versioned index pin, the human stakeholder is platform engineer shipping faq-index@sha256:a1b2 to staging, and the incident id you design against is DEPLOY-EMPTY-INDEX-5. Re-state the oracle in your notes — kubectl rollout status shows ready; /readyz 200 only when index pin matches — and keep the invariant visible: readyz fails if index digest ≠ pinned digest; rollback restores previous digest in < 2 min. Track ready_ratio == 1 and citation_miss_rate ≤ 0.02 during rollout as the scoreboard. Surface under change control: GET /readyz. If you only have forty minutes, finish the fixture for new pods serve empty index while old pods terminate — citation miss spike before polishing UI. Promotion language stays ternary: promote, hold, or roll back based on evidence, not hope.

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Before you start

Why this matters

Name the dashboard row or log line platform engineer shipping faq-index@sha256:a1b2 to staging opens first during DEPLOY-EMPTY-INDEX-5. It must include a correlation id and a bounded label from ready_ratio == 1 and citation_miss_rate ≤ 0.02 during rollout. If telemetry is missing, write whether you promote, hold, or roll back — and why hold is the default.

In the wild

See how this idea shows up as a product and a company — then come back to the lesson. Skills transfer across vendors.

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Page assessment

Answer from memory. Completion is saved from this evidence, not from opening the next page.

1. Can you jump from alert to DEPLOY-EMPTY-INDEX-5-class evidence?
2. Do labels stay low-cardinality?
3. Is missing telemetry treated as hold?

All responses are required.