Migrate Durable Functions to Durable Task Scheduler

Step-by-step guide for migrating Azure Durable Functions apps from existing backend storage providers to the Durable Task Scheduler (DTS).

Before You Start

⚠️ Critical Prerequisites

1. Drain in-flight orchestrations. DTS does not import state from other backends. All running orchestrations must complete or be terminated before switching.
2. .NET apps must use isolated worker model. DTS does not support the in-process hosting model. If your app uses in-process (Microsoft.Azure.WebJobs.Extensions.DurableTask), migrate to isolated worker first.
3. Identity-based auth only. DTS uses Microsoft Entra ID / managed identity — no shared keys or connection string secrets. Plan for RBAC setup.

Step 1: Identify Your Current Backend

Inspect your host.json to determine which backend you're migrating from: