I have a production server running SQL Server 2008 Web Edition, and it has to keep running 24x7 with almost no down time, and it's the time for us to move to a more advanced server hardware, also it's a good chance to move to SQL Server 2012 Enterprise.
Now my question, how can I do this migration without taking the database down at all? Like for example setting something between the two servers as replication or so, so I have exactly identical database up-to-second on both servers, then I can just take the main services down for 1 minute, changing the IP address of the database connection from old server to new server and I be sure that the new server has identical copy of the old one.
I can't go with backup/restore approach as it will take time more than acceptable period, that's why I need something which guarantee identical databases exactly as if I am doing backup/restore. 5 minutes could be the max affordable downtime.
The database size is about 100GB.
New server is running 2012 Enterprise, and old server is running 2008 Web
I can exceptionally archive records from the database and minimize its size down to 20GB like.
I have the option to upgrade my SQL Server 2008 Web edition to Enterprise edition if this will help with more solutions, like replication maybe?