This WhitePaper introduces the AlwaysOn Availability Groups concepts that are central for configuring and managing one or more availability groups in SQL Server 2012. For a summary of the benefits offered by availability groups and an overview of AlwaysOn Availability Groups terminology, see AlwaysOn Availability Groups (SQL Server).

An availability group supports a failover environment for a discrete set of user databases, known as availability databases, that fail over together. An availability group supports a set of primary databases and one to four sets of corresponding secondary databases. Secondary databases are not backups. Continue to back up your databases and their transaction logs on a regular basis.

More information on: http://msdn.microsoft.com/en-us/library/ff877884.aspx

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