{"abstract":"Route failover excludes already attempted upstreams.","category":"Network routing","checks":4,"contract":"Bounded offline decision model: route failover excludes already attempted upstreams. Inputs are already validated protocol fields; the explicit fixtures define the supported policy, not a complete protocol implementation.","contract_signature":"healthy, attempted","evaluation_group":"xh-route-failover-excludes-already-attempted-upstreams","failed_approach":"The attempted repair uses `[h for h in attempted if h in healthy]` and still violates a separate fixture.","family":"xh-route-failover-excludes-already-attempted-upstreams","id":"FA-7141","implementations":{"attempt":{"sha256":"06d051cdd34e55c38bbceafd02296ba220a198ee9730c3b58d27d117ee71365c","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport ipaddress\nimport re\nfrom urllib.parse import urlsplit, urljoin\nN = 1\nobservations = []\ndef solve(healthy, attempted):\n    return [h for h in attempted if h in healthy]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve(['a', 'b'], ['a']), ['b'])\", \"check('fixture 2', solve(['a'], []), ['a'])\", \"check('fixture 3', solve([], ['a']), [])\", \"check('fixture 4', solve(['a'], ['a']), [])\"]\nfor _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:\n    exec(_line)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"db1fb477ebd13b14c5d7c51542a7bfbdc76182539f691b04398e34ce0a221c1d","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport ipaddress\nimport re\nfrom urllib.parse import urlsplit, urljoin\nN = 1\nobservations = []\ndef solve(healthy, attempted):\n    return healthy\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve(['a', 'b'], ['a']), ['b'])\", \"check('fixture 2', solve(['a'], []), ['a'])\", \"check('fixture 3', solve([], ['a']), [])\", \"check('fixture 4', solve(['a'], ['a']), [])\"]\nfor _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:\n    exec(_line)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":"Bounded deterministic policy model over validated inputs; not a complete protocol stack or an interoperability claim. The five variants rotate the same explicit fixture set. 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.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"xh-route-failover-excludes-already-attempted-upstreams","generated_at":"2026-09-29T14:38:08.717164+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"This deterministic network routing model isolates the route-failover-excludes-already-attempted-upstreams policy at a network component boundary.","root_cause":"The faulty implementation uses `healthy` for the route-failover-excludes-already-attempted-upstreams decision.","sha256":"5e688530a0250ea7e2ea1ce835ff005e3f52c801fcd0e176101ea5ce0ad7a048","title":"Route failover excludes already attempted upstreams · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":48.491,"exit_code":1,"observations":[{"actual":[],"check":"fixture 2","expected":["a"],"passed":false},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":["a"],"check":"fixture 4","expected":[],"passed":false},{"actual":["a"],"check":"fixture 1","expected":["b"],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": [], \"expected\": [\"a\"], \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [\"a\"], \"expected\": [], \"passed\": false}, {\"check\": \"fixture 1\", \"actual\": [\"a\"], \"expected\": [\"b\"], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":40.259,"exit_code":1,"observations":[{"actual":["a"],"check":"fixture 2","expected":["a"],"passed":true},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":["a"],"check":"fixture 4","expected":[],"passed":false},{"actual":["a","b"],"check":"fixture 1","expected":["b"],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": [\"a\"], \"expected\": [\"a\"], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [\"a\"], \"expected\": [], \"passed\": false}, {\"check\": \"fixture 1\", \"actual\": [\"a\", \"b\"], \"expected\": [\"b\"], \"passed\": false}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}