News

Microsoft Goes Live with Azure File Sync Service

• By Kurt Mackie
• July 20, 2018

First unveiled at last year's Microsoft Ignite conference, the Azure File Sync service is now ready for commercial use, Microsoft announced this week.

Organizations can use the Azure File Sync synchronization service to replicate files from an organization's local Windows Server repositories to Microsoft's cloud-based Azure Files service. It facilitates using Azure Files as a centralized file-share repository for access by organizations.

The Azure Files plus Azure File Sync combination enables tiered cloud file storage, also known as "cloud tiering." Under this scheme, organizations can use their local Windows Server file repositories for more frequently accessed files, while less frequently accessed files get stored on Microsoft Azure datacenter infrastructure. End users access these files without perceiving that they are stored locally or stored in the cloud.

Cloud tiering is described as being an "optional feature of Azure File Sync" in Microsoft's "Planning for an Azure File Sync Deployment" document. Files that are "greater than 64 KiB in size can be tiered to Azure Files," according to the document.

Azure File Sync also has a "fast disaster recovery" feature that adds protections against failing servers, according to Microsoft's announcement:

No matter what happens to your local server -- a bad update, damaged physical disks, or something worse, you can rest easy knowing the cloud has a fully resilient copy of your data. Simply connect your new Windows Server to your existing sync group, and your namespace will be pulled down right away for use. 

Currently, Azure File Sync just works with Windows Server 2016 and Windows Server 2012 R2, but Microsoft could support earlier server products if it gets customer requests to that effect. Microsoft is promising that there will be Azure File Sync support for Windows Server 2019, which is expected to arrive later this year. Last month, Microsoft demonstrated the use of Azure Files during its Windows Server Summit online event, which profiled coming Windows Server 2019 features.

The Azure Files service, though, does work with Linux and macOS operating systems, according to Microsoft's Azure Files FAQ document.

Azure File Sync is supported by georedundant storage, which means that it uses a secondary region to assure against disasters. It's currently available in the following regions: Asia East and Southeast, Australia East and Southeast, Canada East and Central, Europe North and West, United Kingdom West and South, and U.S. East, Central and West.

Microsoft added improvements with the general availability release of Azure File Sync. Georedundant storage was one of them. Microsoft also enhanced the service's performance. File uploads got a two-times speed improvement. Disaster recovery speeds improved "4X to 18X (depending on hardware)," according to the announcement. It's also easier now to understand the progress of sync uploads with a "revamped portal experience."

Azure File Sync just supports New Technology File System (NTFS) volumes. There's no support for the Resilient File System (ReFS), File Allocation Table (FAT) or FAT32 file systems. Organizations must download an Azure File Sync agent to synchronize the files.

The synchronization service currently doesn't work when cloud tiering and Windows Server Data Deduplication are used together. The Azure File Sync agent also does not work with servers that use sysprep. It has problems when used in combination with "application-aware, volume-level and bare-metal (BMR) restore options." Azure File Sync also doesn't work with servers that use the NTFS Encrypted File System.

The maximum size of a file share of Azure Files is 5TiB, but Microsoft is working to increase it to 100TiB, according to the Azure Files FAQ document. The service can handle up to "2,000 open handles" when clients try to access the same file simultaneously.

The cost structure associated with using the Azure Files service is fairly complex. There's also a cost for using Azure File Sync.

"The total cost of Azure File Sync (AFS) services is determined by the number of servers that connect to the cloud endpoint (Azure File Share) plus the underlying costs of File storage (including storage and access costs) and outbound data transfer," according to Microsoft's Azure Files pricing page.