FA-10136 / Deployment models / Open access
Replica rollout status: Failed replicas do not degrade rollout · case 01
Failed replicas do not degrade rollout.
ROOT CAUSE
The implementation substitutes if False: for if failed:, so failed replicas do not degrade rollout.
VERIFIED REPAIR
Surface required replica failures.
Unsuccessful approach: The attempted repair substitutes if not failed:. Fixture 2 still yields 'ready' instead of 'degraded'.
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 False: 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 fixture | Actual | Expected | Outcome |
|---|---|---|---|
| fixture 1 | blocked | blocked | Passed |
| fixture 2 | ready | degraded | Failed |
| fixture 3 | progressing | progressing | Passed |
| fixture 4 | progressing | progressing | Passed |
| fixture 5 | progressing | progressing | Passed |
| fixture 6 | ready | ready | Passed |
| fixture 7 | ready | ready | Passed |
| fixture 8 | ready | ready | Passed |
SHA-256 / 2fd3c62997285cad1e05e21df210c1a53e2be6c1afd475fdb516019ed89c6f04
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 not 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 fixture | Actual | Expected | Outcome |
|---|---|---|---|
| fixture 1 | blocked | blocked | Passed |
| fixture 2 | ready | degraded | Failed |
| fixture 3 | degraded | progressing | Failed |
| fixture 4 | degraded | progressing | Failed |
| fixture 5 | degraded | progressing | Failed |
| fixture 6 | degraded | ready | Failed |
| fixture 7 | degraded | ready | Failed |
| fixture 8 | degraded | ready | Failed |
SHA-256 / 4ace869bce5d625370dc534119af7f0c3e28485c110f0c3dabe68c5343cbecec
3 / The verified repair
Exit 0"""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 fixture | Actual | Expected | Outcome |
|---|---|---|---|
| fixture 1 | blocked | blocked | Passed |
| fixture 2 | degraded | degraded | Passed |
| fixture 3 | progressing | progressing | Passed |
| fixture 4 | progressing | progressing | Passed |
| fixture 5 | progressing | progressing | Passed |
| fixture 6 | ready | ready | Passed |
| fixture 7 | ready | ready | Passed |
| fixture 8 | ready | ready | Passed |
SHA-256 / ec4f78ec9cf74394799a50ebfe7fd63525c297579689fdb23b5cdc789a04ad0a
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 2026-09-29T14:38:36.110197+00:00.
Case digest / d08aaf08529aa8d41b7a87ca845ebf4e4f9fb78878976a77fbb7021f4e65f39f