Introduction to Azure Blob Storage
Azure Blob Storage is Microsoft's object storage solution for the cloud. It is optimized to store massive amounts of unstructured data, such as text or binary data. Unstructured data is data that doesn't adhere to a particular data model or definition, such as images, videos, audio files, arbitrary text files, or any type of binary data.
Blob storage is designed to:
- Serve images or documents directly to a browser.
- Store files for direct download.
- Stream video and audio.
- Store data for backup and restore, disaster recovery, and archiving.
- Store data for analysis by an on-premises or hosted Azure service.
Key Concepts
Blobs
A blob is the fundamental entity in Azure Blob Storage. Any collection of binary data can be stored as a blob. Each blob is stored within a container.
Containers
A container is a logical grouping for a set of blobs. You must create a container before you can upload any data to blob storage. Think of a container as a folder in a file system, but with more capabilities.
Storage Accounts
An Azure storage account provides a unique namespace in Azure for your data. Every object that you store in Azure Storage is referenceable by an account-specific address. The combination of the account name and its private access key constitutes the credentials for your storage account.
There are different types of storage accounts, including:
- General-purpose v2 (GPv2) accounts: Offer the latest features and performance for Blob, File, Queue, and Table storage. Recommended for most scenarios.
- Blob storage accounts: Optimized for storing blobs and are ideal for scenarios such as storing images or documents for websites, storing files for direct download, and storing data for backup and restore.
Blob Types
Azure Blob Storage supports three types of blobs:
Block Blobs
Block blobs are optimized for storing large amounts of unstructured data, such as documents, media files, and application data. Block blobs are composed of blocks, and each block can be a different size. A block blob can be up to 190.7 TiB in size.
This is the most common blob type. Use block blobs for:
- Serving images or documents directly to a browser.
- Storing files for direct download.
- Storing data for backup and restore, disaster recovery, and archiving.
- Storing log files.
Append Blobs
Append blobs are similar to block blobs in that they are composed of blocks, but they are optimized for append operations. Append blobs are ideal for scenarios in which data is written sequentially and infrequently, such as logging application data.
Use append blobs for:
- Logging scenarios, like writing logs from a virtual machine.
- Situations where data is appended to a file, like monitoring progress for a long-running operation.
Page Blobs
Page blobs are optimized for random read and write operations. They are suitable for storing IaaS virtual machine disks, database files, and other transactional workloads.
Page blobs are structured as a collection of pages, each up to 512 bytes in size. A page blob can be up to 8 TiB in size. Use page blobs for:
- Storing VHDs (virtual hard disks) for Azure IaaS virtual machines.
- Storing database files.
Common Use Cases
- Serving Images and Documents: Directly serve images, style sheets, JavaScript files, and documents to a web browser.
- File Storage: Store any type of file for direct download by users or applications.
- Video and Audio Streaming: Stream video or audio files directly to any browser or client application.
- Backup and Restore: Store data for backup and restore, disaster recovery, and archiving purposes.
- Data Lake: Store massive amounts of structured, semi-structured, and unstructured data for big data analytics.
- Virtual Machine Disks: Store the VHDs for Azure virtual machines.
Getting Started
To start using Azure Blob Storage, you'll need an Azure subscription and a storage account. Here are the basic steps:
- Create an Azure Storage Account: You can create a storage account through the Azure portal, Azure CLI, or Azure PowerShell.
- Create a Container: Once you have a storage account, you can create containers within it to organize your blobs.
- Upload Blobs: You can upload blobs using various methods:
- Azure Portal: A user-friendly interface for managing your storage.
- Azure Storage Explorer: A cross-platform GUI tool for managing Azure Storage resources.
- Azure SDKs: Libraries for various programming languages (e.g., .NET, Java, Python, Node.js) to interact with Blob Storage programmatically.
- Azure CLI or PowerShell: Command-line tools for automation.
- REST API: Direct HTTP requests to the Blob Storage service.