Replication and redundancy
In order to guarantee stability and high availability, the customer's data in Azure Storage is replicated constantly. The customer may choose between two replication options: either storage within the same datacenter or to a second datacenter. Replication guards the user's data; in the case of hardware failures, the application is preserved. The use of a second datacenter provides security in the case of a catastrophic failure in the location of the primary datacenter. The process of replication warrants that the customer's storage account meets the SLA for storage.
There are four replication options between which the user can choose when creating an Azure Storage account.