Incident response and capstones · Lesson 8 of 12 · 5 min

Handle a stale index

A stale-index incident needs freshness evidence and a safe update plan. Stage a validated index and keep the prior working artifact until the replacement is accepted.

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-incidents-capstones-008.json. Separate the recorded facts from your assumptions.
Hint & worked example
A stale-index incident needs freshness evidence and a safe update plan. Stage a validated index and keep the prior working artifact until the replacement is accepted.
The complete case JSON is read successfully.
```
cat /opt/ai-lab/cases/aiops-incidents-capstones-008.json
```
Common mistake to avoid: Point traffic at an unvalidated rebuild immediately.
2
Isolate the deciding signal
Select the candidate_validated field from the case JSON. What does it establish—and what does it not establish?
Hint & worked example
Validate the revision-42 candidate before switching away from revision 39.
A successful JSON query isolates candidate_validated.
```
jq .candidate_validated /opt/ai-lab/cases/aiops-incidents-capstones-008.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: validate-fresh-index, change-without-evidence, or ignore-the-signal. Save that one code followed by a newline in /home/learner/lab/aiops-incidents-capstones-008-decision.txt.
Hint & worked example
Validate the revision-42 candidate before switching away from revision 39.
The decision artifact contains the correct code, not just a matching command in history.
```
printf '%s\n' 'validate-fresh-index' > /home/learner/lab/aiops-incidents-capstones-008-decision.txt
```
Common mistake to avoid: Point traffic at an unvalidated rebuild immediately.

Understand the pattern

A stale-index incident needs freshness evidence and a safe update plan. Stage a validated index and keep the prior working artifact until the replacement is accepted.

Interpret the evidence

Validate the revision-42 candidate before switching away from revision 39.

A tempting mistake

Point traffic at an unvalidated rebuild immediately.

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-incidents-capstones-008.json

{
  "fixture": "Fictional training data; not a live measurement.",
  "source_revision": 42,
  "index_revision": 39,
  "candidate_revision": 42,
  "candidate_validated": false
}

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

$ jq .candidate_validated /opt/ai-lab/cases/aiops-incidents-capstones-008.json

false

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

$ printf '%s\n' 'validate-fresh-index' > /home/learner/lab/aiops-incidents-capstones-008-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 “validate-fresh-index” to stop being the justified action. Do not silently replace missing evidence with a guess.

Explain it

What does the evidence in “Handle a stale index” justify?Point traffic at an unvalidated rebuild immediately.Make the change now and gather the missing evidence afterward.Validate the revision-42 candidate before switching away from revision 39.

Apply it elsewhere

A colleague concludes: “Point traffic at an unvalidated rebuild immediately.” What should you do?Treat this fixture as a live measurement.Reject that conclusion; return to the case evidence and its stated limits.Accept it because the training command completed.

Keep the momentum.

Complete the lab, then explain and apply the pattern.

Next: Prepare a model rollback 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