Document Details

In PowerShell:

In PowerShell:

In PowerShell:

In PowerShell:

In PowerShell:

   Replace the following values:

   - *\<app-name>* with the name of your web app.

   > [!TIP]
   > If you use PowerShell console to run the commands, escape the strings in the `--generic-configurations` argument in this step and the next step. For example: `--generic-configurations '{\"acrUseManagedIdentityCreds\": true'`

1. (Optional) If your app uses a [user-assigned managed identity](overview-managed-identity.md#add-a-user-assigned-identity), make sure the identity is configured on the web app and then set the `acrUserManagedIdentityID` property to specify its client ID:

   

When your app runs, the App Service app settings are injected into the process as environment variables automatically. You can verify container environment variables with the URL `https://<app-name>.scm.azurewebsites.net/Env`.

If your app uses images from a private registry or from Docker Hub, credentials for accessing the repository are saved in environment variables: `DOCKER_REGISTRY_SERVER_URL`, `DOCKER_REGISTRY_SERVER_USERNAME`, and `DOCKER_REGISTRY_SERVER_PASSWORD`. Because of security risks, none of these reserved variable names are exposed to the application.

::: zone pivot="container-windows"
For IIS or .NET Framework (4.0 or later) based containers, credentials are injected into `System.ConfigurationManager` as .NET app settings and connection strings automatically by App Service. For all other language or framework, they're provided as environment variables for the process, with one of the following prefixes:

- `APPSETTING_`
- `SQLCONTR_`
- `MYSQLCONTR_`
- `SQLAZURECOSTR_`
- `POSTGRESQLCONTR_`
- `CUSTOMCONNSTR_`

::: zone-end

::: zone pivot="container-linux"

This method works both for single-container apps or multi-container apps, where the environment variables are specified in the *docker-compose.yml* file.

::: zone-end

## Use persistent shared storage

::: zone pivot="container-windows"

You can use the *C:\home* directory in your custom container file system to persist files across restarts and share them across instances. The *C:\home* directory is provided to enable your custom container to access persistent storage.

When persistent storage is disabled, writes to the *C:\home* directory aren't persisted across app restarts or across multiple instances. When persistent storage is enabled, all writes to the *C:\home* directory persist. All instances of a scaled-out app can access them. Any existing files already present on the persistent storage when the container starts overwrite any contents in the *C:\home* directory of the container.

The only exception is the *C:\home\LogFiles* directory. This directory stores the container and application logs. This folder always persists upon app restarts if [application logging is enabled](troubleshoot-diagnostic-logs.md?#enable-application-logging-windows) with the **File System** option, whether or not persistent storage is enabled. In other words, enabling or disabling the persistent storage doesn't affect the application logging behavior.

By default, persistent storage is *enabled* on Windows custom containers. To disable it, set the `WEBSITES_ENABLE_APP_SERVICE_STORAGE` app setting value to `false` by using the [Cloud Shell](https://shell.azure.com). In Bash: