If your application is connecting to an AlwaysOn availability group (AG) on different subnets, setting MultiSubnetFailover=true provides faster detection of and connection to the (currently) active server. For more information about SqlClient support for Always On Availability Groups, see SqlClient Support for High Availability, Disaster Recovery.
Assembly: System.Data (in System.Data.dll)
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.