muthukkumaran Kaliyamoorthy (1/28/2015)
Yes, Correct. Server A & B old - SQL 2012. And need to move it to server C & D new - SQL2014.
So, you have two options
The first option involves joining ServerC and ServerD to the same Windows Server Failover Cluster as ServerA and ServerB.
You then restore a backup of the large database onto C and D and then join the instances to the same Availability group as A and B. Once the database has synchronised you failover the group to either C or D and the database is at SQL Server 2014.
To clean up you remove A and B from the AlwaysOn group and then if necessary remove the servers from the Windows Server Failover Cluster.
The second option involves setting up C and D in a new Windows Server Failover Cluster (which it sounds like you may have already done) and creating a cross cluster migration. There is a document provided by Microsoft on how to achieve this, you can find it at this link.
-----------------------------------------------------------------------------------------------------------
"Ya can't make an omelette without breaking just a few eggs" 😉