# Audit the claim

Canonical URL: <https://datadriven.io/problems/audit-the-claim-the-vendor-diagram-says-the-flink-job-deliv-4918ee44>

Domain: Pipeline Design · Difficulty: medium

## Problem

Audit the claim. The vendor diagram says the Flink job delivers exactly-once via 2PC, but the revenue dashboard's numbers double after every checkpoint recovery. Apply the section's across-which-boundary audit: name the boundary where the engine's guarantee ends and pick a repair so the new sink actually carries the property its name claims.

## Related

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