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SQL Server 2012 Upgrade Technical Guide
Plan for Backups
A backup of each database in an instance, including system databases, is the keystone
of an upgrade plan. Even when you upgrade to a new server by using a side-by-side
method, you should still take backups. Perform backups at the following points in the
upgrade process:
Make a backup of the user databases and data after all users are out of the
system and before the upgrade process has begun. Do nothing until this is
completed. Back up all system databases at this point. These backups form the
databases of record, marking the final versions of your old environment. If you
can, copy these backups to a different server and make sure that they can be
easily accessed even in a complete server-down situation. Make sure that the
media is intact so that you can restore the backups if necessary.
When the upgrade is complete, but before you do any configurations or
changes, perform backups under SQL Server 2012. This lets you easily roll back
to a point where the SQL Server 2005/2008/2008 R2 upgrade completed
successfully but where an error was introduced after that point.
After you make any changes to the SQL Server 2012 databases and
configuration, but before allowing acceptance testing on the new SQL Server
2012 instance, take full database backups again. If the testers consider the
upgrade a success, these backups will be the initial backups for your new
environment. If testing finds errors but they are not serious enough to cause a
rollback, you can restore from these initial backups to revert the database to its
original state, ready for a second round of acceptance testing. Then apply
required changes and repeat the backup process. When testing is complete, still
back up all databases before rolling out to production. These backups then
capture the final state of the database before they are put into production.
Important: Make sure that either the Windows Server installation media with
the appropriate keys or good backups of the Windows Server installation image
are available for a potential reinstall. You can rebuild SQL Server only if Windows
is stable and in a state to have applications installed on it.
It might seem that these backups are too many and will consume lots of disk space, but
you can delete most of them after the upgrade to SQL Server 2012 is completed. It is a
good practice to perform all of them, just in case an unexpected issue requires a
restore at any point in time.
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SQL Server 2012 Upgrade Technical Guide
Upgrading Both Windows and SQL Server
Because SQL Server 2012 requires Windows Server 2008 R2 SP1, you might be tempted
to combine a SQL Server 2012 upgrade with an upgrade from Windows Server
2003/2008 to Windows Server 2008 R2 SP1 to reduce the downtime of two major
upgrades into one downtime event. However, upgrading both at the same time can
introduce a significant new variable into the SQL Server 2012 upgrade plan, increase
the risk of failure, and increase the cost of rolling back. Therefore, a decision to
combine these two should be made carefully.
Note: If you decide to change the operating system at the same time as the SQL
Server upgrade, we recommend that you design and execute a test of the upgrade
and operating system changes in a test or staging environment before you try it in
production.
Some considerations when you upgrade both Windows and SQL Server:
If the legacy instances of SQL Server 2005/2008/2008 R2 are on Windows Server
2003 or Windows Server 2008, an upgrade of Windows is required because SQL
Server 2012 is only supported on Windows Server 2008 R2 SP1 and later. In that
case, consider a side-by-side upgrade to a separate server, especially if the
legacy server is older and does not meet the minimum requirements for SQL
Server 2012.
If the legacy instances of SQL Server 2000/2005/2008/2008 R2 are on Windows
Server 2003, be aware that SQL Server 2000 is not supported under Windows
Server 2008. Therefore, if you are currently using SQL Server 2000 and plan to
upgrade the same server to Windows Server 2008, upgrade your SQL Server
2000 instance to SQL Server 2005/2008/2008 R2 before upgrading to Windows
Server 2008 R2 SP1. This process will translate into two outages, but if you
upgrade to Windows Server 2008 R2 SP1 first, SQL Server 2000 instances will not
be supported.
If a legacy instance of SQL Server 2000 is running on Windows Server 2000,
consider using a multistep process. For example, you might upgrade Windows
Server 2000 to Windows Server 2003, then SQL Server 2000 to SQL Server
2005/2008/2008 R2, then Windows Server 2003 to Windows Server 2008 R2 SP1,
and then the legacy SQL Server to SQL Server 2012.
If you are upgrading to Windows Server 2008 R2 SP1 and the server is currently
running SQL Server 2005, make sure that you apply SQL Server 2005 SP4 or later
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SQL Server 2012 Upgrade Technical Guide
versions before the Windows operating system upgrade; otherwise, you might
encounter problems.
If you will reuse the existing server and upgrade Windows Server, depending on
which version of Windows that you start with and which is the final destination,
you could perform an in-place upgrade. This approach might also require
installing a fresh version of Windows Server. If you perform a fresh install of
Windows Server, make sure that all SQL Server databases are backed up, that all
settings are known, and that all users are scripted out.
Windows Server 2008 and 2008 R2 both have an installation option called Core.
Core is basically a locked-down, minimal version of Windows Server that does
not have an interface other than a command line. SQL Server 2012 supports only
Windows Server 2008 R2 Core.
There are two kinds of virtualization with a Windows Server 2008/2008 R2
installation: with Hyper-V and without Hyper-V. SQL Server is supported on both
types. As a rule, a server that is used for production database data should be
dedicated to SQL Server to reduce the risk of another process bringing the SQL
Server down. Unless a server must run virtual machines that will host SQL Server,
install Windows Server 2008/2008 R2 without Hyper-V. (Going without Hyper-V
also means that Windows administrators have one less feature to worry about
when patching for security.) If Windows Server 2008/2008 R2 is installed with
Hyper-V, apply the final Hyper-V Release to Manufacturing (RTM) patch. For
more information, see:
o
The articles
Hyper-V Update for Windows Server 2008 x64 Edition
(KB950050)
(http://www.microsoft.com/en-
us/download/details.aspx?displaylang=en&id=18567) or
Hyper-V Update
for Windows Server 2008 (KB950050)
(http://www.microsoft.com/en-
us/download/details.aspx?DisplayLang=en&id=3273) in the Microsoft
Knowledge Base.
o
For Hyper-V on Windows Server 2008 R2, see
The Windows Server 2008 R2 Hyper-V web site
(http://www.microsoft.com/en-us/server-cloud/windows-
server/hyper-v.aspx)
The white papers
Running SQL Server 2008 in a Hyper-V
Environment
(http://download.microsoft.com/download/d/9/4/d948f981-926e-
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