FAILURE MAP
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FA-10151 / Deployment models / Open access

Replica rollout status: Unavailable replicas count toward readiness · case 01

Unavailable replicas count toward readiness.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The implementation substitutes if False: for if available < desired:, so unavailable replicas count toward readiness.

THE FAILURE

The implementation substitutes if False: for if available < desired:, so unavailable replicas count toward readiness.

Unsuccessful approach: The attempted repair substitutes if available <= desired:. Fixture 6 still yields 'progressing' instead of 'ready'.

Case contract

Report blocked on invalid specification, degraded on failed required replicas, progressing when observed generation lags, progressing when updated or available counts are below desired, otherwise ready. Zero desired is ready when observed.

Why this case matters

An offline model of replica rollout status, suitable for testing build and release tooling without external services.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(valid, failed, observed, generation, updated, available, desired):
    if not valid: return 'blocked'
    if failed: return 'degraded'
    if observed < generation: return 'progressing'
    if updated < desired: return 'progressing'
    if False: return 'progressing'
    return 'ready'
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve(False, False, 1, 1, 1, 1, 1), 'blocked')
check('fixture 2', solve(True, True, 1, 1, 1, 1, 1), 'degraded')
check('fixture 3', solve(True, False, 0, 1, 1, 1, 1), 'progressing')
check('fixture 4', solve(True, False, 1, 1, 0, 1, 1), 'progressing')
check('fixture 5', solve(True, False, 1, 1, 1, 0, 1), 'progressing')
check('fixture 6', solve(True, False, 1, 1, 1, 1, 1), 'ready')
check('fixture 7', solve(True, False, 1, 1, 0, 0, 0), 'ready')
check('fixture 8', solve(True, False, 2, 1, 2, 2, 1), 'ready')
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
fixture 1blockedblockedPassed
fixture 2degradeddegradedPassed
fixture 3progressingprogressingPassed
fixture 4progressingprogressingPassed
fixture 5readyprogressingFailed
fixture 6readyreadyPassed
fixture 7readyreadyPassed
fixture 8readyreadyPassed

SHA-256 / 3a1809c486a41fa016e0b4e0184b4609363908e383b115ec0c1108313f64ee48

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(valid, failed, observed, generation, updated, available, desired):
    if not valid: return 'blocked'
    if failed: return 'degraded'
    if observed < generation: return 'progressing'
    if updated < desired: return 'progressing'
    if available <= desired: return 'progressing'
    return 'ready'
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve(False, False, 1, 1, 1, 1, 1), 'blocked')
check('fixture 2', solve(True, True, 1, 1, 1, 1, 1), 'degraded')
check('fixture 3', solve(True, False, 0, 1, 1, 1, 1), 'progressing')
check('fixture 4', solve(True, False, 1, 1, 0, 1, 1), 'progressing')
check('fixture 5', solve(True, False, 1, 1, 1, 0, 1), 'progressing')
check('fixture 6', solve(True, False, 1, 1, 1, 1, 1), 'ready')
check('fixture 7', solve(True, False, 1, 1, 0, 0, 0), 'ready')
check('fixture 8', solve(True, False, 2, 1, 2, 2, 1), 'ready')
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
fixture 1blockedblockedPassed
fixture 2degradeddegradedPassed
fixture 3progressingprogressingPassed
fixture 4progressingprogressingPassed
fixture 5progressingprogressingPassed
fixture 6progressingreadyFailed
fixture 7progressingreadyFailed
fixture 8readyreadyPassed

SHA-256 / d6556578da504165148fd6a8d8b2c0462f53349c3ec155c3f6977989125fd789

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 8 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

Member access is invitation-based. Sign in with your invited account to inspect the repair.

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Verification & scope

This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:38:36.320415+00:00.

Case digest / 5a289b6a8820be76676a8577f1ff8ffb3a3487d2e2ba930041017c18f7fd8d1e