HA and DR Protection
The following slides highlight three ways you can provide high availability and disaster recovery protection for SQL Server in the cloud.
Use Windows Server Failover Clustering in the Cloud
Because SQL Server is a business-critical application, you need to provide high-availability protection for it, regardless of where it is deployed. In the cloud, you need to protect SQL from downtime if the cloud instance or the cloud provider fails. While most cloud providers offer multiple availability zones — generally separate and redundant data centers or computing resources — they do not offer shared storage (i.e., a SAN), which is required to support traditional Windows Server Failover Clustering (WSFC) across cloud-availability zones.
You can use SANless software instead of a SAN to create a high-availability cluster using WSFC. You can configure redundant SQL Server application instances in different cloud availability zones. When a failure occurs, WSFC will coordinate SQL application restart to the second environment in a different availability zone.