Microsoft’s Azure platform is a significant player in the cloud storage market.
According to Microsoft figures, by the start of 2024, Azure storage clocked up more than 100 exabytes of data reads and writes a month, which translated to more than a quadrillion monthly transactions. This reflects global growth in cloud storage, but also Azure’s increasingly comprehensive storage offering.
Although Azure is – understandably – most closely associated with Microsoft workloads, the supplier now provides a far wider range of storage options.
This extends to niches such as object storage and storage for containers, as well as support for virtual machines, virtual desktops, and non-Microsoft technologies including Oracle and SAP.
The key Azure storage options include block, file and object storage. The main choices are Azure Files, Azure Blobs, Azure Elastic SAN, Azure Managed Disks (including Premium Disk SSD), and Azure Container Storage. Microsoft also has a partnership with NetApp, for Azure NetApp Files, and compatibility with NetApp appliances and platforms.
In practice, on-premise Microsoft customers and Azure users are likely to use multiple Azure storage options. Microsoft has also built up partnerships with a range of specialist storage suppliers, including Qumulo (Blob storage), Commvault (cyber resilience) and Pure Storage (including for its Portworx container-focussed data management platform).
Here, we drill down into the most common Azure storage options.
Azure Files
Azure Files provides managed cloud file shares. These use industry-standard file systems, including SMB and NFS. But, Files also supports the Azure Files Rest API. Files can mount on Linux, Windows and Mac on-premise systems, as well as cloud applications.
Microsoft describes Azure Files as suited to organisations that want to “lift and shift” an application to the cloud, or replace or add to on-premise NAS devices or file servers. This allows on-premise applications to store data in the cloud.
Files also works where a cloud application uses native file system application programming interfaces (APIs) to share data with other Azure-based applications.
Users can access data on Files anywhere, using a URL and shared access token, and Files can also integrate with Active Directory using Azure Files AD Authentication. In addition, Microsoft positions Files for application development, and to provide persistent volumes for containerised applications.
Costs range from £0.012 per month per used GiB for Cool storage to £0.1332 for premium, for local redundancy storage (LRS) in the cheapest UK region, namely UK South. Microsoft offers an Azure storage calculator to drill down into specific options.
Azure NetApp files is also a NAS replacement, albeit separate to Azure Files. Microsoft says it’s best suited for “difficult to migrate” workloads. These include Posix-compliant Windows and Linux applications, SAP Hana, high-performance computing infrastructure and enterprise web apps, among others.
Azure Elastic SAN
Elastic SAN allows enterprises to create a storage area network (SAN) in the Azure Cloud. By moving to the cloud, organisations can scale their storage more easily, as well as add cloud capabilities such as high availability and redundancy.
As a storage area network, Elastic SAN can support multiple applications via the iSCSI protocol. This includes Azure VMs and Kubernetes services, as well as SQL and other databases. Elastic SAN is designed for large-scale, I/O-intensive workloads.
The 1TiB Premium Base Unit, with LRS, starts at £71.912 per month for provisioned resources, plus charges of £0.071 a month.
Azure Managed Disks
Azure Disks are one of the simplest storage formats on Microsoft’s cloud infrastructure. Disks are simply virtual hard disks for persistent data storage.
These are best suited to applications that use a native file system to read and write data. Typically, Disks are attached directly to a virtual machine and there is no need to access that data from outside the VM. So, Disks are often used where organisations move VMs from their on-premise hardware to the cloud.
However, Managed Disks come in a range of types, including ultra disks, premium solid state drives – themselves available in Premium SSD and Premium SSD v2 – standard SSDs, and hard drives.
Ultra disks have a maximum throughput of 10,000 MBps and max IOPS of 400,000, with a maximum disk size of 65,536GiB. Premium v2 has a maximum throughput of 1,200MBps and 80,000 IOPS, with the same capacity; “standard” premium has 900MBps and 20,000 IOPS, and a capacity of 32,767GiB.
Microsoft claims a higher than five nines availability (and a 0% annualised failure rate) for Disks. Pricing for LRS starts at £0.57 a month for a 4GiB drive and £0.03 per mount per month. Zone-redundant storage starts at £0.86 for 4GiB.
Azure Blob Storage
Blob is Azure’s implementation of object storage. Azure Blob Storage allows for the storage of very large amounts of unstructured data, for random access, and where organisations want to be able to access data from any location.
Blob storage is also suitable for image serving and video and audio streaming, as well as backup, disaster recovery and archiving.
Blob storage comes as General Purpose v2 – the standard storage tier – Block blob, a premium tier for applications with highs transaction volumes, or that need low latency, and Page blobs for OS, VM data disk and database storage.
Microsoft also positions Blob as the storage element of data lakes and for big data analytics, with Blob storage providing capacity for Azure Data Lake Storage Gen2, for cloud-based analytics. Here, Blob supports a hierarchical file system, while retaining the tiering, high availability and disaster recovery features of object storage.
Applications access objects in Blob storage is via HTTP and HTTPs, as well as API.
Blob storage costs range from £0.00137 per GB per month for the Archive tier to £0.14227 for Premium, for the first TB of capacity.