Using LDT with SQL AlwaysOn

To guard a directory with an LDT (Live Data Transformation) policy, you must temporarily close all of the files in that directory. In an SQL Server AlwaysOn environment, this may entail temporarily stopping the SQL Server service on the node that is being guarded. Once the directory is guarded, then you can start the SQL Server service immediately.

It is important to remember that the SQL Server AlwaysOn replication standard operating procedures.

• If one SQL Server service is taken offline for any reason, then once it is brought back on line, it takes the SQL Server a moment to re-synchronize the database nodes.

• The longer that secondary service was down, and the more inserts/updates and deletes that occurred on the still active node during that downtime, then the longer the synchronization period takes.

• During that synchronization period, any attempted fail over results in the SQL Server warning that data loss may occur if the fail over continues. However, once the SQL Server has completed re-synchronizing that secondary node, then any fail over is safe and does not result in loss of data.