Cloud computing enables new scenarios for applications requiring scalable, durable, and highly available storage for their data – which is exactly why Microsoft developed Azure Storage. In addition to making it possible for developers to build large-scale applications to support new scenarios, Azure Storage also provides the storage foundation for Azure Virtual Machines, a further testament to its robustness.
Azure Storage is massively scalable, so we can store and process hundreds of terabytes of data to support the big data scenarios required by scientific, financial analysis, and media applications. Or you can store the small amounts of data required for a small business website. Wherever your needs fall, you pay only for the data we’re storing. Azure Storage currently stores tens of trillions of unique customer objects, and handles millions of requests per second on average.
Azure Storage is elastic, so we can design applications for a large global audience, and scale those applications as needed - both in terms of the amount of data stored and the number of requests made against it. wepay only for what we use, and only when we use it.
Azure Storage uses an auto-partitioning system that automatically load-balances your data based on traffic. This means that as the demands on your application grow, Azure Storage automatically allocates the appropriate resources to meet them.
Azure Storage is accessible from anywhere in the world, from any type of application, whether it’s running in the cloud, on the desktop, on an on-premises server, or on a mobile or tablet device. You can use Azure Storage in mobile scenarios where the application stores a subset of data on the device and synchronizes it with a full set of data stored in the cloud.
Azure Storage supports clients using a diverse set of operating systems (including Windows and Linux) and a variety of programming languages (including .NET, Java, and C++) for convenient development. Azure Storage also exposes data resources via simple REST APIs, which are available to any client capable of sending and receiving data via HTTP/HTTPS.
Standard Storage Accounts
A standard storage account gives you access to Blob storage, Table storage, Queue storage, and File storage:
- Blob storage stores file data. A blob can be any type of text or binary data, such as a document, media file, or application installer.
- Table storage stores structured datasets. Table storage is a NoSQL key-attribute data store, which allows for rapid development and fast access to large quantities of data.
- Queue storage provides reliable messaging for workflow processing and for communication between components of cloud services.
- File storage (Preview) offers shared storage for legacy applications using the standard SMB 2.1 protocol. Azure virtual machines and cloud services can share file data across application components via mounted shares, and on-premise applications can access file data in a share via the File service REST API. File storage is available by request via the Azure Preview page.
For users with large amounts of unstructured data to store in the cloud, Blob storage offers a cost-effective and scalable solution. You can use Blob storage to store content such as:
- Social data such as photos, videos, music, and blogs
- Backups of files, computers, databases, and devices
- Images and text for web applications
- Configuration data for cloud applications
- Big data, such as logs and other large datasets
Every blob is organized into a container. Containers also provide a useful way to assign security policies to groups of objects. A storage account can contain any number of containers, and a container can contain any number of blobs, up to the 500 TB capacity limit of the storage account.
Blob storage offers two types of blobs, block blobs and page blobs (disks). Block blobs are optimized for streaming and storing cloud objects, and are a good choice for storing documents, media files, backups etc. A block blob can be up to 200 GB in size. Page blobs are optimized for representing IaaS disks and supporting random writes, and may be up to 1 TB in size. An Azure virtual machine network attached IaaS disk is a VHD stored as a page blob.
For very large datasets where network constraints make uploading or downloading data to Blob storage over the wire unrealistic, you can ship a hard drive to Microsoft to import or export data directly from the data center using the Azure Import/Export Service. You can also copy blob data within your storage account or across storage accounts.
Modern applications often demand data stores with greater scalability and flexibility than previous generations of software required. Table storage offers highly available, massively scalable storage, so that your application can automatically scale to meet user demand. Table storage is Microsoft’s NoSQL key/attribute store – it has a schemaless design, making it different from traditional relational databases. With a schemaless data store, it's easy to adapt your data as the needs of your application evolve. Table storage is easy to use, so developers can create applications quickly. Access to data is fast and cost-effective for all kinds of applications. Table storage is typically significantly lower in cost than traditional SQL for similar volumes of data.
Table storage is a key-attribute store, meaning that every value in a table is stored with a typed property name. The property name can be used for filtering and specifying selection criteria. A collection of properties and their values comprise an entity. Since Table storage is schemaless, two entities in the same table can contain different collections of properties, and those properties can be of different types.
You can use Table storage to store flexible datasets, such as user data for web applications, address books, device information, and any other type of metadata that your service requires. You can store any number of entities in a table, and a storage account may contain any number of tables, up to the capacity limit of the storage account.
Like Blobs and Queues, developers can manage and access Table Storage using standard REST protocols, however Table Storage also supports a subset of the OData protocol, simplifying advanced querying capabilities and enabling both JSON and AtomPub (XML based) formats.
For today's Internet-based applications, NoSQL databases like Table storage offer a popular alternative to traditional relational databases.
In designing applications for scale, application components are often decoupled, so that they can scale independently. Queue storage provides a reliable messaging solution for asynchronous communication between application components, whether they are running in the cloud, on the desktop, on an on-premises server, or on a mobile device. Queue storage also supports managing asynchronous tasks and building process workflows.
A storage account can contain any number of queues. A queue can contain any number of messages, up to the capacity limit of the storage account. Individual messages may be up to 64 KB in size.
File Storage (Preview)
Many legacy applications rely on file shares, a dependency that has complicated moving these applications to the cloud. File storage offers cloud-based file shares, so that you can migrate legacy applications to Azure quickly and without costly rewrites.
Applications running in Azure virtual machines or cloud services can mount a File storage share to access file data, just as a desktop application would mount a typical SMB share. Any number of application components can mount and access the File storage share simultaneously.
Since a File storage share is a standard SMB 2.1 file share, applications running in Azure can access data in the share via file sytem I/O APIs. Developers can therefore leverage their existing code and skills to migrate existing applications. IT Pros can use PowerShell cmdlets to create, mount, and manage File storage shares as part of the administration of Azure applications.
Like the other Azure storage services, File storage exposes a REST API for accessing data in a share. On-premise applications can call the File storage REST API to access data in a file share. This way, an enterprise can choose to migrate some legacy applications to Azure and continue running others from within their own organization. Note that mounting a file share is only possible for applications running in Azure; an on-premise application may only access the file share via the REST API.
Distributed applications can also use File storage to store and share useful application data and development and testing tools. For example, an application may store configuration files and diagnostic data such as logs, metrics, and crash dumps in a File storage share so that they are available to multiple virtual machines or roles. Developers and administrators can store utilities that they need to build or manage an application in a File storage share that is available to all components, rather than installing them on every virtual machine or role instance.