Warehouse automation (MFS) · MFS BlackBox
Duplicate telegram retransmission (retry storm)
- Default severity
- Major
- Finding code:
- MFS_DUPLICATE_TELEGRAM_SEND
- Engine version:
- 1.3.0
What this finding means
MFS BlackBox reports this finding with the default severity “Major”.
About the engine: Material Flow System telegram sequence & telegram buffer auditor
How to fix it
Investigate missing / late ACKs that trigger retransmission; tune the resend interval and max retries in the channel configuration.
How ERP Preflight detects it
The analysis is deterministic: the same exported files and the same knowledge snapshot always produce the same findings. No SAP system connection is required — you upload exports.
- Engine
- MFS BlackBox
- Accepted formats
- JSON, CSV, XLSX
- What to export
MFS telegram log: CSV/TSV/pipe log with a header row (type, hu_id, cp, to_cp, seq_no, sender_plc, receiver_plc, status, time_sec/timestamp, wt_id, plc_release; EDGE,<from>,<to> rows declare conveyor topology), the same table as the first worksheet of an XLSX workbook, or JSON {'telegrams': [...], 'conveyor_edges': [[from, to]], 'configuration': {ack_timeout_seconds, max_retries, heartbeat_timeout_seconds, completion_timeout_seconds, recurrence_threshold}}. Inline payloads are bounded by the service payload limit; delimited logs of any size (multi-GB) are streamed through POST /api/v1/analyze/stream and processed line by line with bounded memory.
- Required input
- At least one telegram with a 'type'
- Evidence
- Each finding points to the artifact path, line and column, the code snippet and the SHA-256 of the uploaded file. Findings without such a pointer are demoted to confidence UNKNOWN.
- Confidence
- The verdict rests on your artifacts only. Each finding carries a confidence class (VERIFIED, RULE_DERIVED, INFERRED or UNKNOWN) that shows how strong the evidence is.
- Target releases of the engine
- S4H_2022, S4H_2023, S4HANA_CLOUD_2402, S4HANA_CLOUD_2408
Related findings
- CriticalFirst causal divergence in the incident timeline
- CriticalLIFE / heartbeat telegram gap exceeds the timeout
- CriticalHU moved between non-adjacent conveyor points
- CriticalTelegram not acknowledged within timeout
- CriticalWarehouse task confirmed for a wrong HU / destination or twice
- MajorMalformed telegram record
Terms used on this page
Background reading
- SAP EWM Material Flow System (MFS): diagnosing PLC telegram errors and sequence gapsHow SAP Extended Warehouse Management communicates with programmable logic controllers (PLCs) over MFS telegrams, and how to diagnose handshake timeouts, sequence mismatches and channel resets.