We are upgrading WSS 3.0 from Server 2003 R2 x64 to Sharepoint Foundation 2010 on Server 2008 R2 x64 And the questions follow:

Can we migrate the databases first (in order to keep Sharepoint up) from our current MSSQL 2003 R2 x86 server to our newly created MSSQL 2008 R2 x64 server and point our WSS 3.0 to it?

I'm hoping to do this, while another colleague spins up the new Sharepoint servers on the side (running on Server 2008 R2 x64), so that in the end, when the Sharepoint servers are built, we can migrate from the old Sharepoint servers on Server 2003 x64 to the new Sharepoint Servers on 2008 R2 x64.

Is this possible?  Migrate DB from old SQL to new SQL, point old MSS to new SQL DB, spin up new MSS, point new MSS to new SQL DB, decommission old SQL and old MSS servers?

What is the best approach to doing so with minimal downtime and most reliability?

Any help would be greatly appreciated!

• Edited by itmondsply 10 hours 46 minutes ago

Have a look on below given earlier discussed thread that might helps you:

Moving WSS 3.0 databases to another database server on another OS : https://social.technet.microsoft.com/Forums/office/en-US/d9887f4a-c5b3-42cf-9e9b-ceecc5e280b5/moving-wss-30-databases-to-another-database-server-on-another-os?forum=sharepointadminlegacy

Migrating Windows Sharepoint Services 3.0 from Windows 2003 x86 / MSEE to Windows 2008 R2 x64 / SQL Server 2008: http://sharepoint.stackexchange.com/questions/36394/migrating-windows-sharepoint-services-3-0-from-windows-2003-x86-msee-to-window

Best approach to upgrade MOSS 2007 from windows 2003 32-bit env. to windows 2008 64-bit env: http://www.go4sharepoint.com/Forum/best-approach-upgrade-moss-2007-windows-22904.aspx

Upgrade from 32bit SQL Server to 64bit SQL Server: http://blogs.msdn.com/b/cindygross/archive/2009/07/07/x64-windows-upgrade-from-32bit-sql-server-to-64bit-sql-server.aspx

Hope it helps you!

If the scope is to migrate to SharePoint 2010 then create the new environment with SharePoint 2010 and upgrade the content db from MOSS2007 to SPS2010.

https://technet.microsoft.com/en-us/library/cc303309(v=office.14).aspx 

If the scope is to move all content databases to a new server and use the same SharePoint version you have this complete article that covers the following two scenarios

- To move all databases to a database server that has a different name, use the Move all databases to a different database server procedure.
- To move all databases to an identically named or upgraded database server, use the Move all databases to a database server that has the same name procedure.

https://technet.microsoft.com/en-us/library/cc512725(v=office.12).aspx