Microsoft wants to replicate the on-premises experience of a SAN appliance in Azure as a managed service, a rare block storage offering among cloud storage vendors.
The company unveiled Azure Elastic SAN during this week's Microsoft Ignite 2022 event, taking place in Seattle and online. Azure Elastic SAN is currently available in preview.
For storage administrators looking to squeeze more performance out of their databases, Microsoft unveiled Azure Premium SSD v2 Disk Storage, also in preview. Microsoft claimed the new storage offering can provide sub-millisecond disk latencies and high IOPS for workloads including enterprise databases and big data analytics applications.
SAN-sational cloud storage
The Azure Elastic SAN service replicates the experience of a SAN appliance using software, enabling customers to pool Azure block storage resources into a more performant network rather than as singular, interconnected drives.
Azure Elastic SAN resources are accessible through iSCSI, enabling interoperability with existing SAN appliances and volumes as well a migration path to the cloud, according to Microsoft. The service also provides cloud replication and availability through the zone-redundant storage feature. This capability enables replication across three other zones in an Azure region without additional SAN array setup or replication policies.
The debut of a SAN SaaS for Microsoft Azure makes sense to offer to customers due to the vendor's massive corporate buy-in and footprint in the enterprise technology space, said Ray Lucchesi, president and founder of Silverton Consulting.
Traditional on-premises storage vendors have software-defined storage options aimed at tiering storage to the cloud or enabling cloud bursting for applications, but they do not have an equivalent to Azure Elastic SAN, he said.
Ray LucchesiPresident and founder, Silverton Consulting
"A lot of enterprises have a [number] of SANs on-prem to avoid vendor lock-in. This might appeal to them," Lucchesi said.
The drawback, he added, comes from moving a massive amount of data and the associated infrastructure within a typical SAN into the cloud. There's also an exit cost if an enterprise considers switching hyperscalers or moving back on-premise due to workload demands.
A direct competitor offering a similar product is StorPool on AWS, which similarly targets massive scale-out block storage provided by a SAN, said Marc Staimer, president of Dragon Slayer Consulting. AWS' own io2 Block Express volumes can provide scale-out block capabilities but requires a DIY approach to match the capabilities and performance of Azure's managed service.
There isn't a huge demand for such block storage services, Staimer said, but enterprises considering a cloud move could likely use Azure Elastic SAN to keep up the performance of their current on-premises databases.
"Microsoft really needs [the service] for their database offerings and database consolidation," he said.
StorPool's one-time closest competitor for scale-out block storage was Excelero, which was absorbed into Nvidia when the chipmaker purchased the vendor in early 2021.
The Azure Premium SSD v2 offering similarly promises fast performance and IOPS over other Azure disk products, including the prior Azure Premium SSD service and the cheaper hard disk drive tier.
The new service, according to Microsoft, enables customers to make performance adjustments with independent throughput and IOPS without needing to purchase additional storage capacity as required in its past disk products.
The service can support a maximum disk size of about 64 TB and a peak IOPS of 80,000, an increase from the original Premium SSD offering of 20,000 IOPS at its peak and about 32 TB of storage per disk. Price is dependent on user performance requests.
The preview is currently available in only the U.S. East and West Europe Azure regions. Specific drawbacks to the service include no support for snapshots, no support for Azure Disk Encryption for VMs, and no support for Azure Backup and Azure Site Recovery Services, according to Microsoft.
Tim McCarthy is a journalist living on the North Shore of Massachusetts. He covers cloud and data storage news.