Name of Failure:

[BF] test-4.2-standalone — "RHEL 8 MMAPv1" variant (drivers-tools). Fails in bootstrap mongo-orchestration before any test runs.

Link to task:

https://spruce.corp.mongodb.com/task/drivers_tools_tests_storage_engines__os_fully_featured~rhel8_storage_engine~mmapv1_test_4.2_standalone_5d52ccdbb60f6e1749a71ce787c9f8f7da861b15_26_11_10_21_51_15/logs?execution=0

Context of when and why the failure occurred:

Long-standing, deterministic failure — not a flake: 0 successful runs out of 75 over the last nine months (0/27 Feb–Aug 2026, 0/48 Aug–Nov 2026), every activated run system-failed identically. Likely never passed.

The task starts a MongoDB 4.2.25 standalone with storageEngine: "mmapv1"; mongod exits immediately with Location18656: Cannot start server with an unknown storage engine: mmapv1 and orchestration returns HTTP 500. MMAPv1 was removed in server 4.2, so this combination cannot start. Drivers dropped MMAPv1 testing for 4.1+ in DRIVERS-497; this variant still runs only test-4.2-standalone.

Impact: the variant is permanently red on mainline — CI noise that masks any new real failure on this task.

Stack trace:

2026-11-11T18:41:39.754+0000 I  STORAGE  [initandlisten] exception in initAndListen: Location18656: Cannot start server with an unknown storage engine: mmapv1, terminating
2026-11-11T18:41:39.754+0000 I  CONTROL  [initandlisten] shutting down with code:100
...
2026-11-11 18:41:39,826 [ERROR] mongo_orchestration.servers:389 - Could not start Server. Please find server log below.
OSError: Process started, but died immediately
...
2026-11-11 18:41:39,828 [DEBUG] mongo_orchestration.apps:55 - send_result(500)
...
urllib.error.HTTPError: HTTP Error 500: Internal Server Error
Command 'subprocess.exec' in function 'bootstrap mongo-orchestration' (step 1.1 of 2) failed: process encountered problem: exit code 1.
Task completed - FAILURE.