Lesson 8

Now that you have completed this module, you should be able to:

1. Describe changes to initialization parameters needed to support the features in Oracle
2. Add a network node in Net Assistant
3. Modify the tnsnames.ora file
4. Describe how to start a Net listener service with Oracle Enterprise Manager
5. Start a listener with line commands
6. Describe the uses of the Net Configuration Assistant

The Net Assistant is not used in Oracle Database 12c for setting parameters during installation. It was deprecated in earlier versions and replaced by the **Oracle Net Configuration Assistant (NETCA)** in Oracle Database 10g and later. Here's a breakdown: Net Assistant:

1. Deprecated in earlier versions of Oracle Database.
2. Not included in the Oracle Database 12c installation media.
3. Its functionality has been replaced by NETCA.

NETCA:

1. Introduced in Oracle Database 10g.
2. The current and recommended tool for setting network parameters during Oracle Database installation on all platforms.
3. Provides a graphical interface for configuring network settings like listener ports, database aliases, and connection protocols.
4. Offers more advanced features than Net Assistant.

Therefore, when installing Oracle Database 12c, you should use NETCA to configure network parameters. It provides a more modern and robust experience compared to the deprecated Net Assistant.

Providing a history of changes to your Oracle database parameters is not only a DBA best practice, it is absolutely required in a mission-critical production environment. Back when Oracle parameters were kept in a flat file on the server (the init.ora file) tracking changes was difficult.
However, once Oracle introduced the "spfile" feature it became easier to track changes to initialization parameters. Below are two common techniques for tracking Oracle initialization parameters:

1. auditing, and
2. using the extra-cost AWR method.

If you have purchased the extra cost performance pack and diagnostic pack (and have access to the AWR dba_hist_parameter table), it is easy to run a script to track all changes to your initialization parameters.

Oracle Net Manager enables you to configure Oracle Net Services for an Oracle home on a local client or server host. You can use Oracle Net Manager to configure the following network components:

1. Listeners: Create and configure listeners to receive client connections.
2. Naming: Define connect identifiers and map them to connect descriptors to identify the network location and identification of a service. Oracle Net Manager supports configuration of connect descriptors in local tnsnames.ora files or a centralized directory service.
3. Naming methods: Configure the ways connect identifiers are resolved to connect descriptors.
4. Profiles: Configure preferences for enabling and configuring Oracle Net features on the client or server.

This module has concentrated on the new features of Net and Oracle8i as they relate to Net installation and configuration.

1. Oracle8i made new Java-based OEM screens and had added a new look and feel to the GUI interfaces in contrast to Oracle 7
2. Oracle8i had introduced important new tnsnames.ora parameters, including ADDRESS_LIST, LOAD_BALANCE, FAILOVER, SOURCE_ROUTE, INSTANCE_NAME, and SERVICE_NAME.
3. Oracle8i now allows for failover functionality when using OPS of multiple listeners. With failover, Oracle automatically re-establishes lost client connections.
4. When you specify multiple addresses for a service name, the SOURCE_ROUTE parameter determines the order in which the addresses are searched.
5. Oracle is replacing the Server Manager (svrmgrl) with SQL*Plus. To issue SQL*Plus commands, you need to connect as sysdba.
6. Oracle has implemented connection load balancing for Oracle Shared Server. MTS has been discontinued since Oracle 9i.in a similar fashion to that used in OPS. The new load balancing feature uses the MTS and routes incoming connections to the least recently called dispatcher.

In a Real Application Clusters environment, multiple instances can be associated with a single database service. Clients can override Oracle's connection load balancing by specifying a particular instance by which to connect to the database. INSTANCE_NAME specifies the unique name of this instance. In a single-instance database system, the instance name is usually the same as the database name.

Click the Quiz link below to test your understanding of the concepts presented in this module.
Network Administration- Quiz