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--- title: How to disable functions in Azure Functions description: Learn how to disable and enable functions in Azure Functions. ms.topic: conceptual ms.date: 03/12/2024 ms.custom: devx-track-csharp --- # How to disable functions in Azure Functions This article explains how to disable a function in Azure Functions. To *disable* a function means to make the runtime ignore the event intended to trigger the function. This ability lets you prevent a specific function from running without having to modify and republish the entire function app. You can disable a function in place by creating an app setting in the format `AzureWebJobs.<FUNCTION_NAME>.Disabled` set to `true`. You can create and modify this application setting in several ways, including by using the [Azure CLI](/cli/azure/), [Azure PowerShell](/powershell/azure/), and from your function's **Overview** tab in the [Azure portal](https://portal.azure.com). > [!NOTE] > Changing application settings causes your function app to restart by default across all hosting plans. For zero-downtime deployments when changing settings, use the [Flex Consumption plan](flex-consumption-plan.md) with [rolling updates as the site update strategy](flex-consumption-site-updates.md). For other hosting plans, see [optimize deployments](functions-best-practices.md#optimize-deployments) for guidance on minimizing downtime. ## Disable a function Use one of these modes to create an app setting that disables an example function named `QueueTrigger`: ### [Portal](#tab/portal) Use the **Enable** and **Disable** buttons on the function's **Overview** page. These buttons work by changing the value of the `AzureWebJobs.QueueTrigger.Disabled` app setting. The function-specific app setting is created the first time a function is disabled.  Even when you publish to your function app from a local project, you can still use the portal to disable functions in the function app. > [!NOTE] > Disabled functions can still be run by calling the REST endpoint using a master key. To learn more, see [Run a disabled function](#run-a-disabled-function). This means that a disabled function still runs when started from the **Test/Run** window in the portal using the **master (Host key)**. ### [Azure CLI](#tab/azurecli) In the Azure CLI, you use the [`az functionapp config appsettings set`](/cli/azure/functionapp/config/appsettings#az-functionapp-config-appsettings-set) command to create and modify the app setting. The following command disables a function named `QueueTrigger` by creating an app setting named `AzureWebJobs.QueueTrigger.Disabled` and setting it to `true`. ```azurecli-interactive az functionapp config appsettings set --name <FUNCTION_APP_NAME> \ --resource-group <RESOURCE_GROUP_NAME> \ --settings AzureWebJobs.QueueTrigger.Disabled=true ``` To re-enable the function, rerun the same command with a value of `false`. ```azurecli-interactive az functionapp config appsettings set --name <myFunctionApp> \ --resource-group <myResourceGroup> \ --settings AzureWebJobs.QueueTrigger.Disabled=false ``` ### [Azure PowerShell](#tab/powershell) The [`Update-AzFunctionAppSetting`](/powershell/module/az.functions/update-azfunctionappsetting) command adds or updates an application setting. The following command disables a function named `QueueTrigger` by creating an app setting named `AzureWebJobs.QueueTrigger.Disabled` and setting it to `true`. ```azurepowershell-interactive Update-AzFunctionAppSetting -Name <FUNCTION_APP_NAME> -ResourceGroupName <RESOURCE_GROUP_NAME> -AppSetting @{"AzureWebJobs.QueueTrigger.Disabled" = "true"} ``` To re-enable the function, rerun the same command with a value of `false`. ```azurepowershell-interactive Update-AzFunctionAppSetting -Name <FUNCTION_APP_NAME> -ResourceGroupName <RESOURCE_GROUP_NAME> -AppSetting @{"AzureWebJobs.QueueTrigger.Disabled" = "false"} ``` --- ## Disable functions in a slot By default, app settings also apply to apps running in deployment slots. You can, however, override the app setting used by the slot by setting a slot-specific app setting. For example, you might want a function to be active in production but not during deployment testing. It's common to disable timer triggered functions in slots to prevent simultaneous executions. To disable a function only in the staging slot: ### [Portal](#tab/portal) Navigate to the slot instance of your function app by selecting **Deployment slots** under **Deployment**, choosing your slot, and selecting **Functions** in the slot instance. Choose your function, then use the **Enable** and **Disable** buttons on the function's **Overview** page. These buttons work by changing the value of the `AzureWebJobs.<FUNCTION_NAME>.Disabled` app setting. This function-specific setting is created the first time you disable the function. You can also directly add the app setting named `AzureWebJobs.<FUNCTION_NAME>.Disabled` with value of `true` in the **Configuration** for the slot instance. When you add a slot-specific app setting, make sure to check the **Deployment slot setting** box. This option maintains the setting value with the slot during swaps. ### [Azure CLI](#tab/azurecli) ```azurecli-interactive az functionapp config appsettings set --name <FUNCTION_APP_NAME> \ --resource-group <RESOURCE_GROUP_NAME> --slot <SLOT_NAME> \ --slot-settings AzureWebJobs.QueueTrigger.Disabled=true ``` To re-enable the function, rerun the same command with a value of `false`. ```azurecli-interactive az functionapp config appsettings set --name <myFunctionApp> \ --resource-group <myResourceGroup> --slot <SLOT_NAME> \ --slot-settings AzureWebJobs.QueueTrigger.Disabled=false ``` ### [Azure PowerShell](#tab/powershell) Azure PowerShell currently doesn't support this functionality. --- To learn more, see [Azure Functions Deployment slots](functions-deployment-slots.md). ## Run a disabled function You can still cause a disabled function to run by supplying the master access key (`_master`) in a REST request to the endpoint URL of the disabled function. In this way, you can develop and validate functions in Azure in a disabled state while preventing them from being accessed by others. Using any other type of key in the request returns an HTTP 404 response. [!INCLUDE [functions-master-key-caution](../../includes/functions-master-key-caution.md)] To learn more about the master key, see [Understand keys](function-keys-how-to.md#understand-keys). To learn more about calling non-HTTP triggered functions, see [Manually run a non HTTP-triggered function](functions-manually-run-non-http.md). ## Disable functions locally Functions can be disabled in the same way when running locally. To disable a function named `QueueTrigger`, add an entry to the Values collection in the local.settings.json file, as follows: ```json { "IsEncrypted": false, "Values": { "FUNCTIONS_WORKER_RUNTIME": "python", "AzureWebJobsStorage": "UseDevelopmentStorage=true", "AzureWebJobs.QueueTrigger.Disabled": true } } ``` ## Considerations Keep the following considerations in mind when you disable functions: + When you disable an HTTP triggered function by using the methods described in this article, the endpoint can still be accessed when running on your local computer and [in the portal](#run-a-disabled-function). + At this time, function names that contain a hyphen (`-`) can't be disabled when running on Linux. If you plan to disable your functions when running on Linux, don't use hyphens in your function names. ## Next steps This article is about disabling automatic triggers. For more information about triggers, see [Triggers and bindings](functions-triggers-bindings.md).