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