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title Tutorial - Manually failover an Azure IoT hub
description Learn how to perform a manual failover of your IoT hub to a different region and then return it to the original region.
author cwatson-cat
manager lizross
ms.service azure-iot-hub
services iot-hub
ms.topic tutorial
ms.date 11/17/2022
ms.author cwatson
ms.custom
mvc
mqtt
build-2025

Tutorial: Perform manual failover for an IoT hub

Manual failover is a feature of the IoT Hub service that allows customers to failover their hub's operations from a primary region to the corresponding Azure geo-paired region. The manual failover feature is offered to customers at no additional cost for IoT hubs created after May 18, 2017.

Note

Manual failover can be done in the event of a regional disaster or an extended service outage. You can also perform a planned failover to test your disaster recovery capabilities, although we recommend using a test IoT hub rather than one running in production.

In this tutorial, you perform the following tasks:

[!div class="checklist"]

  • Using the Azure portal, create an IoT hub.
  • Perform a failover.
  • See the hub running in the secondary location.
  • Perform a failback to return the IoT hub's operations to the primary location.
  • Confirm the hub is running correctly in the right location.

For more information about manual failover and Microsoft-initiated failover with IoT Hub, see Reliability in Azure IoT Hub.

Prerequisites

  • An Azure subscription. If you don't have an Azure subscription, create a free account before you begin.

Create an IoT hub

[!INCLUDE iot-hub-include-create-hub]

Perform a manual failover

Note

There is a limit of two failovers and two failbacks per day for an IoT hub.

  1. Navigate to your IoT hub in the Azure portal.

  2. Under Hub settings on the navigation menu, select Failover.

    :::image type="content" source="./media/tutorial-manual-failover/trigger-failover-01.png" alt-text="Screenshot showing IoT Hub properties pane.":::

  3. On the Failover pane, you see the Current location and the Failover location listed for your IoT hub. The current location always indicates the location in which the hub is currently active. The failover location is the standard Azure geo-paired region that is paired to the current location. You cannot change the location values.

  4. At the top of the Failover pane, select Start failover.

    :::image type="content" source="./media/tutorial-manual-failover/trigger-failover-02.png" alt-text="Screenshot showing Manual Failover pane.":::

  5. In the confirmation pane, fill in the name of your IoT hub to confirm it's the one you want to failover. Then, to initiate the failover, select Failover.

    :::image type="content" source="./media/tutorial-manual-failover/trigger-failover-03-confirm.png" alt-text="Screenshot showing Manual Failover confirmation pane.":::

    The amount of time it takes to perform the manual failover is proportional to the number of devices that are registered for your hub. For example, if you have 100,000 devices, it might take 15 minutes, but if you have five million devices, it might take an hour or longer.

    While the manual failover process is running, a banner appears to tell you a manual failover is in progress.

    If you select Overview to view the IoT hub details, you see a banner telling you that the hub is in the middle of a manual failover.

    After it's finished, the current and failover regions on the Manual Failover page are flipped and the hub is active again. In this example, the current location is now WestCentralUS and the failover location is now West US 2.

    :::image type="content" source="./media/tutorial-manual-failover/trigger-failover-06-finished.png" alt-text="Screenshot showing failover is complete.":::

    The overview page also shows a banner indicating that the failover is complete and the IoT Hub is running in the paired region.

Perform a failback

After you have performed a manual failover, you can switch the hub's operations back to the original primary region. This action is called a failback. If you have just performed a failover, you have to wait about an hour before you can request a failback. If you try to perform the failback in a shorter amount of time, an error message is displayed.

A failback is performed just like a manual failover. These are the steps:

  1. To perform a failback, return to the Failover pane for your IoT hub.

  2. Select Start failover at the top of the Failover pane.

  3. In the confirmation pane, fill in the name of your IoT hub to confirm it's the one you want to failback. To then initiate the failback, select Failover.

    :::image type="content" source="./media/tutorial-manual-failover/trigger-failover-03-confirm.png" alt-text="Screenshot showing Manual Failover confirmation pane.":::

    After the failback is complete, your IoT hub again shows the original region as the current location and the paired region as the failover location, as you saw originally.

Clean up resources

To remove the resources you've created for this tutorial, delete the resource group. This action deletes all resources contained within the group. In this case, it removes the IoT hub and the resource group itself.

  1. Click Resource Groups.

  2. Locate and select the resource group that contains your IoT hub.

  3. If you want to delete the entire group and all the resources in it, select Delete resource group. When prompted, enter the name of the resource group and select Delete to confirm the action.

    If you only want to delete specific resources from the group, check the boxes next to each resource you want to delete then select Delete. When prompted, type yes and select Delete to confirm the action.

Next steps

In this tutorial, you learned how to configure and perform a manual failover, and how to initiate a failback.

Advance to the next tutorial to learn how to configure your device from a back-end service.

[!div class="nextstepaction"] Configure your devices