Database Reference
In-Depth Information
Chapter 13
Clusterware and Database Upgrades
by Syed Jaffar Hussain
Whenever Oracle announces a new version, the million-dollar question facing every organization and every DBA
is whether to upgrade their current (and mostly stable) environment. There is little doubt that the prospect of an
upgrade gives you, as a DBA, butterflies in your stomach and the feeling that it will take a lot of hard work to make the
process successful. It's hardly surprising that many organizations are afraid to accept the risks of an upgrade.
The objective of this chapter is to explain the key elements that drive an organization to consider upgrading.
It also offers the best practices, tips, and tricks to upgrade your current Oracle Grid Infrastructure (GI) and databases
to the new Oracle 12c.
Typically, people reject the risk of an upgrade for the following main reasons:
•
The organization's legacy application doesn't support the new Oracle release.
•
The organization doesn't want to face new challenges that might materialize after an upgrade.
•
There are no experienced or skilled DBAs to perform such an important action.
•
Resources, such as a nonproduction environment to simulate the change before taking them
into production, are lacking.
Here are a few key factors that drive an organization or DBA to consider an upgrade of their existing environment
nevertheless:
•
To stay up to date with the latest technology as dictated by standards or security policies
•
To address or fix some of the critical issues encountered in the current environment
•
To leverage the enhancements of the new version to improve database performance or
flexibility
•
To continue to use Oracle Support; Oracle will stop supporting the older version in terms of
providing bug fixes, patches, etc., after a grace period or a version's extended support policy
Configuration
This chapter used the following setup configuration to demonstrate an Oracle Clusterware 11gR2 (11.2.0.3) and
Database upgrade to Oracle 12c (12.1.0.0.2):
•
Oracle 11gR2: 11.2.0.3
•
RedHat Enterprise Linux 5: OS
