# Find the boundary

Canonical URL: <https://datadriven.io/problems/find-the-boundary-the-flink-jobs-exactly-once-guarantee-en-3eecaf55>

Domain: Pipeline Design · Difficulty: medium

## Problem

Find the boundary. The Flink job's exactly-once guarantee ends at every cross-system sink it writes to, and the four sinks on the canvas are not all equivalent. Reroute the analytics consumer's incoming connection so it reads from a sink whose cross-system boundary is end-to-end idempotent in the scenario as labeled, without further configuration the canvas has not granted.

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