Separate delivery IDs from maintenance event IDs in the Scheduled Events preview

Source facts

Scheduled Events delivery through Event Grid is a preview that Microsoft does not recommend for production workloads. Its wrapper ID differs from the scheduled event’s EventId, which stays constant as EventStatus changes. Rare duplicate deliveries carry the same wrapper ID and identical payload. Approving a scheduled event permits it to proceed for every VM listed in its Resources array. Microsoft Learn.

Applicability

Evaluate this design only in a preview-approved test environment with event delivery explicitly enabled. Identify the subscribing service, its duplicate-handling storage, and any separate authority to acknowledge maintenance. Keep message receipt distinct from a decision that the listed workloads are ready.

DSE recommendation

Use the Event Grid delivery ID for duplicate detection and retain the Scheduled EventId for lifecycle correlation. Design processing so a repeated delivery does not repeat a disruptive action, while a legitimate later state remains visible. Before implementing acknowledgement, require the controller to resolve and prepare every resource named in the event rather than only the first VM encountered.

Verification

Replay a captured nonsensitive test payload with the same delivery ID and confirm that it is handled as a duplicate. Then exercise later event states and confirm that the lifecycle record is updated rather than discarded. Inspect the entire Resources array in the approval path. Retain the tested identifiers and observed behavior, and do not equate a working preview consumer with approval to operate it in production.

Official references

Microsoft Learn: Scheduled Events in Event Grid. Source reviewed September 9, 2026.