Book Image

Microsoft Windows Azure Development Cookbook

By : Neil Mackenzie
Book Image

Microsoft Windows Azure Development Cookbook

By: Neil Mackenzie

Overview of this book

The Windows Azure platform is Microsoft's Platform-as-a-Service environment for hosting services and data in the cloud. It provides developers with on-demand computing, storage, and service connectivity capabilities that facilitate the hosting of highly scalable services in Windows Azure datacenters across the globe. This practical cookbook will show you advanced development techniques for building highly scalable cloud-based services using the Windows Azure platform. It contains over 80 practical, task-based, and immediately usable recipes covering a wide range of advanced development techniques for building highly scalable services to solve particular problems/scenarios when developing these services on the Windows Azure platform. Packed with reusable, real-world recipes, the book starts by explaining the various access control mechanisms used in the Windows Azure platform. Next you will see the advanced features of Windows Azure Blob storage, Windows Azure Table storage, and Windows Azure Queues. The book then dives deep into topics such as developing Windows Azure hosted services, using Windows Azure Diagnostics, managing hosted services with the Service Management API, using SQL Azure and the Windows Azure AppFabric Service Bus. You will see how to use several of the latest features such as VM roles, Windows Azure Connect, startup tasks, and the Windows Azure AppFabric Caching Service.
Table of Contents (16 chapters)
Microsoft Windows Azure Development Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Creating and using a blob snapshot


The Windows Azure Blob Service supports the creation of read-only snapshots of a blob. A storage account is billed only for those blocks and pages in a snapshot that differ from those in the underlying blob. A blob snapshot is useful in providing a backup for a blob as it can be used to reset the blob to an earlier state. Indeed, multiple snapshots can be made over time allowing a historic record to be kept of changes to a blob.

An important use case for blob snapshots is provided by the Azure Drive feature. An Azure Drive is a page blob comprising an NTFS-formatted VHD that can be attached to a hosted service role instance and accessed as an NTFS drive. To avoid read-write conflicts, a single VHD page blob can be attached to only one instance at a time. However, a blob snapshot is read-only, allowing no possibility of write contention, so an arbitrary number of instances can attach a VHD snapshot simultaneously.

A blob snapshot is created using the CloudBlob...