Do you currently rely on Azure storage GRS (globally redundant storage) to provide a disaster recovery option? Do you realise that Microsoft will only invoke a failover to allow GRS to be used if they are unable to recover an entire availability zone? In the past, there have been multi-hour or day outages, and Microsoft has not enacted a failover. Instead, customers have been unable to access their data.
GRS is excellent if you need to have long-term storage and you can survive without the data for days or possibly weekss. If you need faster access to your data in the event of a failure, then you need to do more than rely on GRS and Microsoft.
When you use GRS Microsoft creates a secondary account that you cannot access in a partner availability zone to the zone your storage account is deployed to. If Microsoft failed over an entire zone, what are the possibilities that the partner zone you are failing over to will have the capacity for the primary deployed resources and the resources from the failed zone? If Microsoft loses an entire zone, baring a severe world-life changing event, it will probably be because of a code change and if they break one entire zone and cannot recover, what is to say they won’t have also have broken the partner zone?
I am sure you use automation such as ARM templates to deploy your applications. Wouldn’t it be great to know that you can deploy your applications to another, unaffected, region or cloud provider and have your data waiting for you?
Wouldn’t it be great if you could tell your finance department they are free to cancel the credit card paying the azure subscription and you can fail over to AWS with a moments notice? Would you like to invoke the “chaos monkey” on a whole cloud provider and be confident that you have the data you need to re-create your entire environment without having to wait for Microsoft to decide to failover an entire availability zone and then fight to allocate the resources?
We are working on a blob storage replication solution that takes away the limitations of blob storage today and adds some innovative features to keep your data available, even if Azure isn’t.