AlwaysOn Availability Groups

I am sure if you have looked in the new features for SQL Server 2012, then you would have noticed “AlwaysOn” being mentioned. On using your favorite search engine, you would have found out that the new SQL Server 2012 instance provides the opportunity to have multiple secondary replicas of your SQL Server instance. On reading further, you find out that you can now have multiple databases failing over to another instance. Oh WOW!! This is what is called Availability Groups in SQL Server 2012!

Before I start outlining what this Wiki page will be covering, let me clarify certain technical terms….

Availability Group – A container for a set of databases, availability databases, that fail over together.
Availability Database – A database that belongs to an availability group.
Availability Replica – An instantiation of an availability group that is hosted by a specific instance of SQL Server and maintains a local copy of each availability database that belongs to the availability group.

Henceforth, I will be referring to the feature as a Availability Group which provides high availability and disaster recovery capabilities for SQL Server. This page will cover various aspects of monitoring and troubleshooting SQL Server 2012 Availability Groups.

SQL Server 2012 has added a number of new logging options for failover cluster instances and availability groups. The different sets of data that can be collected for performing root cause analysis for SQL Server 2012 Availability Groups is documented here.

Useful Links
Books Online – AlwaysOn Availability Groups
http://technet.microsoft.com/en-us/library/hh510230.aspx
AlwaysON – HADRON Learning Series – What Is HADRON
http://blogs.msdn.com/b/psssql/archive/2010/12/07/alwayson-hadron-learning-series-what-is-hadron.aspx
AlwaysON – HADRON Learning Series – New DMVs
http://blogs.msdn.com/b/psssql/archive/2010/12/14/alwayson-hadron-learning-series-new-dmvs.aspx
Who is using AlwaysOn?
http://sqlcat.com/sqlCat/b/msdnmirror/archive/2012/04/17/who-is-using-alwayson.aspx