Overview

It creates a file system that secures data at rest and in-transit.
- Provides SMB interface, client libraries, and REST interface.
Azure VM's and on-prem clients can mount these file shares just as they would any other file share.
It can be used to store:
- Shared application data (config files)
- Diagnostic data (logs, crash dumps, etc.)
- Tools and utilities needed for system administration
Use it to "lift and shift" an application to the cloud which already uses the native file system APIs.
Use it store development and debugging tools that need to be accessed from many virtual machines.

Features

Replace or supplement on-premises file servers:
- Azure Files can be used to completely replace or supplement traditional on-premises file servers or NAS devices.
- Windows, macOS, and Linux can directly mount Azure file shares wherever they are in the world.
- It can also be replicated with Azure File Sync to Windows Servers, (both on-premises or in the cloud), for performance and distributed caching.
Shared application settings: A common pattern for distributed applications is to have configuration files in a centralized location.
- Application instances can load their configuration through the File REST API, and humans can access them as needed by mounting the SMB share locally.
Diagnostic share: An Azure file share is a convenient place for cloud applications to write their logs, metrics, and crash dumps.
- Logs can be written by the application instances via the File REST API, and developers can access them by mounting the file share on their local machine.
Dev/Test/Debug: When developers or administrators are working on VMs in the cloud, they often need a set of tools or utilities.
- Copying such utilities and tools to each VM can be a time consuming exercise.
- By mounting an Azure file share locally on the VMs, a developer and administrator can quickly access their tools and utilities, no copying required.

It allows to centralize organization's file shares in Azure Files, while keeping the flexibility, performance, and compatibility of an on-premises file server.
Azure File Sync transforms Windows Server into a quick cache of your Azure file share.
You can use any protocol that's available on Windows Server to access your data locally, including SMB, NFS, and FTPS.

Azure Files provides two broad approaches to client applications: Server Message Block (SMB) and REST. Within .NET, these approaches are abstracted by the System.IO and WindowsAzure.Storage APIs.

Use it when your application:
- Needs to read/write files via SMBIs running on a device that has access over port 445 to your Azure Files account
- Doesn't need to manage any of the administrative settings of the file share.
- Coding file I/O with Azure Files over SMB is generally the same as coding I/O with any network file share or local storage device.