Lesson 12

This module discussed how to configure Oracle Net. By now, you should have a good idea of how Oracle Network Services fits into a client-server architecture, and you should feel reasonably comfortable configuring a client PC to access a database. You should know how to perform the following tasks:

1. Edit the listener.ora file, and add an entry for another database instance
2. Edit the tnsnames.ora file, and add a new service name for use by client software
3. Use the ping command to verify connectivity to the host
4. Use the tnsping command to verify connectivity to the Oracle Net listener
5. Start and stop the Oracle Net listener
6. Connect to a remote database over the network

As you work more with Oracle, you will find out that there is much more to Oracle Network Services than can be presented in this one module. Oracle Network Services can support several protocols besides TCP/IP as well as Network Topology. You can use a product called Oracle Names to avoid having to configure tnsnames.ora files on each client PC. There also are other, more sophisticated, troubleshooting techniques than those discussed in this module. What you have seen here represents the most common ways that I have seen for configuring Network Services at the various client sites that I have supported.

This module introduced you to the following terms:

1. internal password: The password that you need to use when you issue a CONNECT INTERNAL command from Server Manager.
2. listener: A process that runs on a database server, and listens for incoming requests from clients that want to connect to databases on that server.
3. LU6.2: A networking protocol used in IBM mainframe environments.
4. Oracle Net: Oracle's generic networking protocol, used to connect two databases to each other, or to connect client software to a database server. Oracle Net insulates Oracle and client applications from the underlying network protocol being used.
5. network adaptor: A Oracle Net component that adapts the Oracle Net software for a particular networking protocal. For example, the Oracle Net TCP/IP adaptor allows you to run Oracle Net over a TCP/IP network.
6. ping: A utility used to verify TCP/IP connectivity between two nodes on a network.
7. Oracle Net service: A service under Windows is software that runs in the background, independently of any logged on user. Oracle Net service is a usually a database instance, but could be some other software, that is accessible via Oracle Net.
8. service handler: A Oracle Net related entity that runs in conjunction with the listener to handle connection requests for a database instance.
9. SPX/IPX: A networking protocol used on Novel NetWare networks.
10. TCP/IP: A networking protocal widely used in the UNIX world, and which happens to be the most commonly used protocol by clients that need to connect to Oracle servers.
11. tnsping: A Oracle Net utility used to verify connectivity between a client and a remote listener.

Today, most users choose to create the database with the standard installer interface. In the next module, you will learn about password files, and about how they enable remote administrative access to a database.

While LU6.2 (Logical Unit 6.2) is still technically supported on IBM mainframe environments, its usage has significantly declined in favor of newer and more versatile networking protocols. Here's why:

• Legacy Protocol: LU6.2 was primarily designed for peer-to-peer and distributed transaction processing in the era before widespread adoption of TCP/IP.
• Limitations:
  • LU6.2, as part of IBM's SNA (Systems Network Architecture), has certain limitations compared to modern IP-based protocols.
  • Complex configuration and management.
  • Less flexibility for integrating with modern, non-SNA network environments
• Shift to TCP/IP: Most mainframe environments have embraced TCP/IP as the dominant networking protocol due to:
  • Industry-wide standardization
  • Easier integration with internet-based systems and web-based technologies
  • More robust networking tools and support

When LU6.2 May Still Be Used:

• Legacy Systems: Some older mainframe applications may have been specifically designed to use LU6.2 and might not have been migrated to TCP/IP. In these cases, LU6.2 support remains necessary.
• Specific SNA Interactions: If a mainframe system needs to communicate with other SNA-based systems that haven't adopted TCP/IP, LU6.2 might be required for compatibility.

Overall Trend: The general direction in mainframe environments is a continuous movement towards TCP/IP-based networking. Modern applications and integrations are almost always built on TCP/IP stacks.

Before you move on, click the Quiz link below for another Oracle Oracle Net quiz.
Oracle Net Client Configuration - Quiz