PI/PO Migration Part 5: Testing, Cutover and Decommissioning PO

📌 KEY POINTS
✅ Compare Cloud Integration outputs with PO outputs for the same input messages.
✅ Cutover requires draining in-flight messages in PO before switching senders.
✅ Parallel runs are possible for some outbound scenarios but risky for inbound updates.
✅ Monitoring and alerting must be live from the first message after cutover.
⚠️ Leaving PO channels active after cutover can process messages twice.

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▶ WHERE WE ARE
This final migration part brings interfaces live and retires PO.

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▶ 1. COMPARISON TESTING
Capture representative messages from PO, including edge cases and errors, and process them through the migrated iFlow. Compare outputs field by field or with automated diff tools. Business owners sign off for interfaces with business impact.

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▶ 2. CUTOVER SEQUENCING
For each interface, stop senders or put them in hold, let PO process remaining messages, check that queues and adapters are empty, switch sender endpoints to Cloud Integration, deactivate PO channels, and release senders. Document each step with times.

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▶ 3. PARALLEL RUNS
For read-only or outbound reporting interfaces, running both platforms and comparing outputs can increase confidence. For interfaces that post data in receivers, parallel processing would create duplicates, so they are switched cleanly.

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▶ 4. AFTER GO-LIVE
Cloud Integration monitoring, alerting for failed messages and certificate expiry, and an agreed support model must work from day one. Watch volumes and error rates closely during the first days and keep a rollback plan for the first period where possible.

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▶ 5. DECOMMISSIONING
After a stable period, remove migrated objects from the PO Integration Directory, then archive the repository content for reference. When all waves are complete, decommission the PO system and its infrastructure, ending its cost and security exposure.

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▶ STEP BY STEP

1. Prepare comparison test cases from PO message history.
2. Write a cutover runbook for one interface.
3. Rehearse cutover in a test landscape.
4. Define decommissioning criteria for migrated PO objects.

✅ CHECKPOINT: an interface is cut over with no lost or duplicate messages and its PO objects are deactivated.

After cutting over an order interface, a PO sender channel was left active and polling the same SFTP folder as the new iFlow. Some orders were processed twice. The runbook was updated to deactivate PO channels before activating Cloud Integration polling, and a duplicate check was added at the receiver.

• Switching while messages are in flight.
• Leaving PO channels active.
• Parallel runs for posting interfaces.
• No monitoring at go-live.

• Comparison tests with PO history.
• Runbook with drain and switch steps.
• Deactivate PO channels first.
• Hypercare with alerting.

Interviewers ask how you test, cut over and decommission migrated interfaces without losing or duplicating messages, and when PO can finally be switched off.