Understanding SQL*Net
SQL*Net's New Features
This release of SQL*Net provides a number of new features and enhancements over previous releases. These enhancements include features that
- make SQL*Net easier to configure and use
- provide increased troubleshooting capability
- make SQL*Net networks available to non-database applications.
Performance Improvements
With SQL*Net release 2.3 you can choose to have multiple listeners for a single database and multiple listeners listening for more than one equivalent database. Listener load balancing enables you to distribute connection requests for a database among a number of listeners. With connections distributed among a number of listeners, no single listener is likely to be overburdened, and connection time will be faster. You can also have a many-to-many relationship between listeners and equivalent database instances. For more information about listener load balancing, see Chapter 2.
Ease of Use Enhancements
A number of new features make setting up and maintaining a SQL*Net release 2.3 network easier.
If you create a new network using Oracle Names version 2 and the Dynamic Discovery Option, you may not need to use Oracle Network Manager to create a network definition or extensive configuration files. Even if you add Oracle Names 2.0 and the Dynamic Discovery Option to an existing network, you can reduce the number of configuration files needed and the amount of effort required to add new clients and servers to the network. This option is suitable if the network has a flat naming structure, a single transport protocol, and a limited number of servers. For further information, see Chapter 3 in this manual and the Oracle Names Administrator's Guide.
Through the Listener Control Utility (LSNRCTL) you can set a number of listener parameters using the SET command, or display the parameters using the SHOW command. You can also change the listener password using LSNRCTL. For further information, see Chapter 5 in this manual.
Troubleshooting Features
New diagnostic tools have been added to this release of SQL*Net.
The new Audit Trail feature can be valuable to a network or database administrator, or anyone responsible for monitoring user activity. This feature adds a block of text to existing listener log files every time a connection is attempted by a client. For further information, see Chapter 2 in the Oracle Network Products Troubleshooting Guide.
Trace Route (TrcRoute) is a new utility that allows administrators to discover what path or route a connection is taking from the client to the server. TrcRoute travels as a special type of connect packet. For more information about TrcRoute, see Chapter 5 in the Oracle Network Products Troubleshooting Guide.
Client registration enables you to provide information about a client that is included in the Audit Trail when the client makes service requests. This registration information is captured in the audit trail and can be loaded into database tables for tracking purposes. It may be useful in compiling usage or billing statistics.
The Client Status Monitor is a utility that provides a snapshot of the client's current configuration. Diagnosing connection problems and providing information to Oracle Customer Support are made easier using this tool. The Client Status Monitor also provides access to the SQLNET.ORA Editor, described earlier in this section. For more information about the Client Status Monitor, see Chapter 5 in this manual, and Chapter 4 in the Oracle Network Products Troubleshooting Guide.
Open API
The SQL*Net OPEN API enables developers to create non-database applications that make use of an existing SQL*Net network. Refer to Appendix D for further information.