5
Using Net8 with Multiple Oracle Homes

This chapter describes how you work with multiple Oracle homes and Net8.

Specific topics discussed are:

Multiple Oracle Homes Overview

Previous releases of Oracle for Windows NT and Windows 95 supported only single Oracle homes, allowing you to install and run only one SQL*Net or Net8 version in a single Oracle home directory. For example, you could not install SQL*Net release 2.3.2 and SQL*Net release 2.3.3 or multiple installations of Net8 release 8.0.3 on the same machine.

Releases 8.0.4 and 8.0.5 supports multiple Oracle homes, a feature that allows you to install one or more Net8 releases on the same machine (in multiple Oracle home directories). For example, using multiple Oracle homes, you can install release 8.0.4 products and 8.0.5 products in different Oracle homes on the same machine.

Control Utilities with Multiple Oracle Homes

The Oracle home in which you installed products most recently is the first directory listed in your PATH (primary home). As such, it has priority over the other Oracle home entries in your PATH. If you invoke a control utility, the version of the product invoked will be that stored in the Oracle home listed first in your path.

You can specify a different version of a control utility by:

Specifying the Absolute Path

Oracle Corporation recommends going to the absolute path to the version of the LSNRCTL80, NAMESCTL80, CMCTL80 control utility (ORACLE_HOME\BIN) you want to use prior to starting it.

Changing the Value of PATH

You can change the value of PATH so that the first entry points to the binary files for the product version you want to use by resetting PATH from the:

Oracle Home Selector

Oracle Home Selector is a graphical user interface (GUI) that enables you to edit your environment path to make an appropriate Oracle home directory your primary home. This tool can only be used when you have multiple, active Oracle home directories on a single computer.

Choose Start > Programs > Oracle for Windows NT - HOME_NAME > Oracle Home Selector.

The Oracle Home Selector window appears.

Enter the Oracle home in the drop-down list that you want to be the primary Oracle home.

System Level

The new value you assign to PATH exists until you change the value of PATH again.

To change the value of PATH at the system level:

Choose Start > Settings > Control Panel.

The Control Panel window appears.

Double-click on the System icon.

The System Properties window appears.

Click on the Environment tab.

The System Variables appear.

Edit the value of the PATH in the Systems Variables window and click OK to exit when you are satisfied with the changes you have made.

Command Line

The value of PATH reverts to its previous value when you quit the session.

To change the value of PATH at the command line:

At the command prompt enter:

SETPATH=pathname;%PATH%

where pathname is the full path to the binary files for the products you want to use.

Service Names

Multiple Oracle homes affect the naming conventions for Oracle services. If you have only one Oracle home directory on a machine, there are no differences between the conventions for naming service names in this release and previous releases (that is, no Oracle HOME_NAME is required and the SID is typically the default of ORCL.) However, as you perform subsequent installations into different Oracle home directories you must specify a different Oracle HOME_NAME for each Oracle home directory during installation, which is added to some service names.

Network Listener

To use the version 8 network listener, you may need to change your network configuration in one of your multiple Oracle homes to prevent conflict. For example, you may need to change:

port number on a TCP/IP network
service name on an SPX network
pipe name on a Named Pipes network
KEY for IPC connection

Listener Startup Mode

If any other network listener (for a different Oracle home or Oracle7 network listener) is already started or set up in Automatic Startup mode, the new network listener is installed with Manual Startup mode, and is not started for you. You must start the network listener manually after proper configuration to resolve any possible conflict.

Configuration File Port Numbers

When the network listener, Oracle Names, and Oracle Connection Manager are installed into another Oracle home, the configuration files installed specify the default port numbers. These port numbers may be in conflict with the configuration file of another Oracle home. Ensure each Oracle home contains configuration files (located in ORACLE_HOME\NET80\ADMIN) with unique port number.

Additional Information:

See Appendix E, "Net8 Services and Port Numbers", for default port number assignments.

Oracle Names Server

If you are using multiple Oracle homes on an Oracle Names Server, Oracle Corporation recommends using the more recent version in order to take advantage of new functionality.

Oracle Connection Manager

If you are using multiple Oracle homes on a machine with Oracle Connection Manager, Oracle Corporation recommends using the more recent version in order to take advantage of new functionality.

5 Using Net8 with Multiple Oracle Homes