Azure Storage is excited to announce customer managed Planned Failover for Azure Storage is now available in public preview.

Over the past few years Azure Storage has offered customer managed (unplanned) failover as a disaster recovery solution for geo-redundant storage accounts. This has enabled our users to meet their business requirements for disaster recovery testing and compliance. Planned failover now provides the same benefits while introducing additional benefits to our storage users.

Planned Failover provides the ability to swap your geo primary and secondary region while the storage service endpoints are still healthy. As a result, a user can now failover their storage account while keeping geo-redundancy and with no data loss or additional cost. Users will no longer need to reconfigure geo-redundant storage (GRS) after their planned failover operation which will save them both time and cost. Once the planned failover operation is completed all new writes will be made to your original secondary region, which will now be your primary region.

After the planned failover is complete, the original primary region becomes the new secondary and the original secondary region becomes the new primary.

 There are multiple scenarios where Planned Failover can be utilized including:

Planned disaster recovery testing drills to validate business continuity and disaster recovery.
Recovering from a partial outage that occurs in the primary region where storage is not impacted. For example, if your storage service endpoints are healthy in both regions, but another Microsoft or 3rd party service is facing an outage in the primary region you can failover your storage services. In this scenario, once you failover the storage account and all other services your workloads can continue to work.
A proactive solution in preparation of large-scale disasters that may impact a region. To prepare for a disaster such as a hurricane, users can leverage Planned Failover to failover to their secondary region then failback once things are resolved.

Planned failover supports Blob, ADLS Gen2, Table, File and Queue data. 

Key differences between our customer managed (unplanned) failover and planned failover are highlighted below:

Unplanned Failover

Planned Failover

After an unplanned failover is completed the storage account is converted to Locally Redundant Storage (LRS) and the secondary region becomes the new primary region.

 After a planned failover is completed the storage account remains Geo Redundant Storage (GRS). The secondary region becomes the new primary region, and the primary region becomes the new secondary region.

Once an unplanned failover is initiated the operation begins immediately. Writes that were pending replication to the secondary region (made after the Last Sync Time) will potentially be lost. Users can utilize their Last Sync Time to determine the recovery point of their storage account.

Once a planned failover is initiated the first step is replicating pending writes (writes made after the Last Sync Time) to the secondary region. As a result, the Last Sync Time is caught up before the and there should be no data loss.

Primary use case: a storage related outage in the primary region.

Primary use case: to test the Failover workflow or a non-storage related outage in the primary region.

An unplanned failover can be used when the primary storage endpoints are unavailable (there is a storage related outage on the primary region).

A planned failover works while the primary and secondary storage endpoints are available.

Regions Planned Failover currently supports

Southeast Asia
East Asia
West Europe
France Central
East US 2
Central US
UK South
Australia East
Switzerland North
Switzerland West
India Central
India West

To learn more about Planned Failover and to track the expansion of the preview into additional regions see, How customer managed planned failover works 

Getting started

Getting started is simple, to learn more about the step-by-step process to initiate a planned failover review, Initiate account failover 

The Azure Portal user experience for Planned Failover.

 Feedback

If you have questions or feedback, do not hesitate to reach out at storagefailover@service.microsoft.com

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