22
SQL Server 2012 Upgrade Technical Guide
An in-place upgrade from a 32-bit instance of SQL Server 2005/2008/2008 R2
(x86) to a 64-bit instance of SQL Server 2008 R2 (x64), or vice versa, is not
supported. For more information, see the note in "Extended System Support
(WOW64)" later in this chapter.
Here are the major steps that the SQL Server 2012 Setup program takes when you
perform an in-place upgrade:
1.
The SQL Server 2012 Setup prerequisites—Microsoft .NET Framework 3.5 Service
Pack 1 (SP1) or a later version, SQL Server Native Client, and so on—are
installed. The legacy instance databases continue to be available.
2.
Setup checks for upgrade blocking issues, a small set of issues that will
completely block an upgrade. If it finds any, Setup will list them. You must fix
them and restart the upgrade process.
3.
If a pending restart exists, you will have to restart the computer.
4.
Setup installs the required SQL Server 2012 executables and support files.
5.
Setup stops the legacy SQL Server service. At this point, the legacy instance is no
longer available.
6.
SQL Server 2012 updates the selected component data and objects.
7.
Setup removes the legacy executables and support files in addition to the legacy
SQL Server 2000 R2 tools. Legacy SQL Server 2005/2008/2008 R2 tools are not
removed. (See Chapter 2, "Management and Development Tools," for more
information).
The new instance of SQL Server 2012 is now fully available. The legacy instance of SQL
Server has been replaced and must be reinstalled from a backup if the need arises.
Side-by-Side Upgrade
In a side-by-side upgrade, instead of directly replacing the older instance of SQL Server,
required database and component data is transferred from a legacy instance of SQL
Server 2005/2008/2008 R2 to a separate instance of SQL Server 2012. It is called a
"side-by-side" method because the new instance of SQL Server 2012 runs alongside the
legacy instance of SQL Server, either on the same server or on a different server.
There are two important options when you use the side-by-side upgrade method:
23
SQL Server 2012 Upgrade Technical Guide
You can transfer data and components to an instance of SQL Server 2012 that is
located on a different physical server or on a different virtual machine.
You can transfer data and components to an instance of SQL Server 2012 on the
same physical server.
Both options let you run the new instance of SQL Server 2008 R2 alongside the legacy
instance of SQL Server 2005/2008/2008 R2. Typically, after the upgraded instance is
accepted and moved into production, you can remove the older instance.
Figure 2 shows the before and after states of a side-by-side upgrade on two servers.
Figure 2: A side-by-side upgrade to another server leaves the legacy instance of
SQL Server 2005, SQL Server 2008, or SQL Server 2008 R2 unchanged
You can also use the side-by-side method to upgrade to SQL Server 2012 on the same
server as the legacy instance of SQL Server 2005, SQL Server 2008, or SQL Server 2008
R2. Figure 3 shows a side-by-side upgrade on the same server.
24
SQL Server 2012 Upgrade Technical Guide
Figure 3: Performing a side-by-side upgrade on the same server, leaving both
instances running
Whether a side-by-side upgrade is to a separate instance on the same server or to a
new instance on another server, data must be transferred in what is mostly a manual
process. The result is two instances, legacy and new, that can run side by side.
As just noted, the key point in a side-by-side upgrade is that you must manually
transfer data files and other supporting objects from the older instance of SQL Server
to the instance of SQL Server 2012. The SQL Server 2012 Setup program will not
perform this task. The objects that you must transfer include the following:
Data files
Database objects
SQL Server Analysis Services (SSAS) cubes
Configuration settings
Security settings
SQL Server Agent jobs
SQL Server Integration Services (SSIS) packages
Here are the main steps that you must perform when doing a side-by-side upgrade of
SQL Server 2005, SQL Server 2008, or SQL Server 2008 R2 to SQL Server 2012:
1.
Install a separate instance of SQL Server 2012 on the legacy server or on a
separate server. The legacy instance continues to be available.
2.
Run the SQL Server 2012 Upgrade Advisor against the legacy instance, and
remove any upgrade blocker issues it finds.
25
SQL Server 2012 Upgrade Technical Guide
3.
Stop all update activity to the legacy instance. This might involve disconnecting
all users or forcing applications to read-only activity.
4.
Transfer data, packages, and other objects from the legacy instance to the
instance of SQL Server 2012.
5.
Apply supporting objects such as SQL Server Agent jobs, security settings, and
configuration settings to the new instance of SQL Server 2012.
6.
Upgrade SSIS (and potentially Data Transformation Services—DTS) packages to
SSIS (see Chapter 17, "Integration Services," for more information).
7.
Verify that the new instance supports the required applications by using
validation scripts and user-acceptance tests.
8.
If the new instance passes validation and acceptance tests, redirect applications
and users to the new instance. At this point, the new instance is available and
databases are online.
9.
Keep your legacy instance for data recovery until you are absolutely confident
that no problems exist on your new production database instance.
A side-by-side upgrade to a new server offers the best of both worlds: You can take
advantage of a new and potentially more powerful server and platform, but the legacy
server remains as a fallback if you encounter a problem. This method could also
potentially reduce upgrade downtime by letting you have the new server and instances
tested, up, and running without affecting a current server and its workloads. You can
test and address hardware or software problems encountered in bringing the new
server online without any downtime of the legacy system. Although you would have to
find a way to export data out of the new system to go back to the old system, rolling
back to the legacy system would still be less time-consuming than a full SQL Server
reinstall and restoring the databases, which a failed in-place upgrade would require.
The downside of a side-by-side upgrade is that increased manual interventions are
required, so it might take more preparation time by an upgrade/operations team.
However, the benefits of this degree of control can often be worth the additional effort.
Upgrading SQL Server 2000 to SQL Server 2012
You cannot upgrade a SQL Server 2000 instance or database to SQL Server 2012.
For an in-place upgrade, upgrade the SQL Server 2000 instance to SQL Server
2005, SQL Server 2008, or SQL Server 2008 R2. Then apply SQL Server 2012
Setup.
Dostları ilə paylaş: |