Cloning Basics

Cloning Basics
If you are trying to learn oracle apps dba skills, cloning would be first practical thing would try to learn and try.
So what exactly is cloning ?? Cloning is a process by which you can literally copy all of your Oracle Apps instance to another location and bring it up. The “copied” instance will inherit virtually everything (patches, profiles, data, code etc…) from source instance, hence it is called “cloned” instance. The reason why you would clone an instance are varied. As per official Oracle Metalink note on cloning (Note:230672.1), you would clone:
1. Creating a copy of the production system for testing updates.
2. Migrating an existing system to new hardware.
3. Creating a stage area to reduce patching downtime.
Let us briefly discuss how cloning works.
For example you have a production instance called PROD and want to create a testing instance for developers and others to play around, this instance is called TEST. In this case source instance is PROD and target instance is TEST. As you know oracle apps has three distinct tiers (see my post Apps Architecture), the desktop tier, apps tier, db tier. You would have to first clone your db tier (As Oracle DBAs you must be familier with cloning db). Once target database and listeners are up and running, copy your application tier files and change configuration files to reflect target instance (e.g. hostname, ports etc). This step of configuring your apps tier is the most difficult step until release 11i when adclone,autoconfig and rapidclone came into the picture.
I would suggest you to go through following metalink notes and get your self familiar with cloning. I will discuss in detail about cloning steps in my future posts on cloning.
References:
Note: 216664.1 – FAQ : Cloning Oracle Applications Release 11i
Note 282930 – Cloning Oracle Applications Release 11i
Note ID 230672.1 – Cloning Oracle Applications Release 11i with Rapid Clone