Azure Storage Overview

Azure Storage offers several scalable, nonrelational data storage offerings with a variety of size, performance, disaster recovery, and availability options to accommodate different workload requirements.

Blob Types

Blobs store unstructured data as objects such as binary files (for example, audio, video, and photos) and text files (for example, documents and equipment logs).

Blobs are offered in three types: Block, Append, and Page.

Block blobs can be sized up to 4.75TB, and although random access to data within a Block blob is not supported, Block blobs are transferred in small sections (blocks) and interrupted transfers can continue from the last block successfully transferred.

Append blobs can be sized up to 200GB and are divided into 4MB blocks. They can accept new data, but the individual blocks cannot be updated and deleted; consequently, Append blobs are most useful for storing ongoing streams of data, such as equipment logs.

Page blobs can be up to 1TB and are divided into 512-byte segments, which can be randomly accessed without requiring transfer of the entire Page blob. Page blobs are used for virtual hard drives (VHDs) that are associated with Azure Virtual Machines (VMs).