Flowing on from my previous article Migrating Database Mirroring to an Availability Group I thought it might be worth posting the high level steps that worked for me in converting a SQL Server 2008 R2/Windows 2008 R2 Enterprise Database Mirroring implementation into a two node Availability Group environment with the second

node in a remote data centre.

The high level steps are :-

1. Disable application access to the Primary SQL Server.
2. Backup all databases on the Primary SQL Server.
3. Upgrade the Disaster Recovery SQL Server to SQL Server 2012 inline. Apply SQL 2012 SP1 and latest Cumulative Patch.
4. Add the Windows Clustering feature on the Primary SQL Server and Disaster Recovery SQL Server.
5. Apply the Windows Hotfix KB 2494036, KB 2654347, KB 2687741 on Primary and Disaster Recovery SQL Servers.
6. Configure a Windows Cluster for the Primary and Disaster Recovery SQL Servers
7. Perform set the database mirroring to Safety mode (synchronous) and perform a manual failover of all mirrored databases to the Disaster Recovery SQL Server.
8. Upgrade the Primary SQL Server to SQL Server 2012 inline. Apply SQL 2012 SP1 and latest cumulative patch.
9. Perform a manual failover of all mirrored databases back to the Primary SQL Server.
10. Remove database mirroring from each database.
11. Configure the Availability Group.
12. Configure the Availability Group listener.
13. Apply the Windows Hotfixes KB 2531907, KB 2616514 on Primary and Disaster Recovery SQL Servers.
14. Test the failover of Availability Group to the Disaster Recovery SQL Server and then back to the Primary SQL Server.
15. Set the AG mirroring to asynchronous commit.
16. Configure applications to use the Availability Group Listener virtual network name.
17. Test application connectivity to the Availability Group Listener virtual network name.
18. Perform the shakedown tests of critical application functionality.
19. Go or No Go decision.