SQL Server 2012 AlwaysOn Failover Cluster Instances (FCI) and AlwaysOn Availability Groups provide a comprehensive high availability and disaster recovery solution. Prior to SQL Server 2012, many customers used FCIs to provide local high availability within a data center and database mirroring for disaster recovery to a remote data center. With SQL Server 2012, this design pattern can be replaced with an architecture that uses FCIs for high availability and availability groups for disaster recovery business requirements. Availability groups leverage Windows Server Failover Clustering (WSFC) functionality and enable multiple features not available in database mirroring. This paper details the key topology requirements of this specific design pattern, including asymmetric storage considerations, quorum model selection, quorum votes, steps required to build the environment, and a workflow illustrating how to handle a disaster recovery event in the new topology across participating job roles.
The new spatial features in SQL Server Code-Named “Denali” represent a significant milestone in the evolution of SQL Server spatial data support. New features include support for full globe spatial objects and circular arcs on the ellipsoid, industry firsts for relational database systems.