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Configuration

Verifying Oracle Network Products Setup

Before proceeding with Oracle Network Products configuration, ensure the necessary products have been installed on the server and each of the clients.

To verify proper installation:

  1. Start the Oracle Installer:

    The Software Asset Manager dialog box appears with the currently installed products listed in the right-hand list box:

  2. Verify the following products are in the Products installed on ORACLE_HOME list box:
    On Your Server On Your Client
    SQL*Net Server and SQL*Net Client SQL*Net Client
    Protocol specific adapter Protocol specific adapter
    Oracle Names Server (optional) Oracle Network Manager for Windows
    Note
     SQL*Net Easy Configuration is automatically installed with SQL*Net.
    Note:
     A supported third party network transport layer must also be installed and tested.

  3. Choose the Exit button to exit the Oracle Installer.

    A dialog box appears, asking you if you want exit the Oracle Installer.

  4. Choose Yes.

    The Oracle Installer exits.

  5. Continue to the next section, "Ways to Configure a Network."

Ways to Configure a Network

 Configuring your network can be viewed in two ways:

See section, "Choosing a Configuration Tool," below for further information on which configuration tool works best with your chosen configuration method.

Choosing a Configuration Tool

Choosing a configuration tool depends upon whether or not your network uses Oracle Names.
network without Oracle Names A localized, managed network without Oracle Names requires creating configuration files with either SQL*Net Easy Configuration or Oracle Network Manager.
network with Oracle Names A centralized managed network with Oracle Names with the DDO does not require creating configuration files. If you are using SQL*Net for the first time, and are willing to accept all default parameters, with the Dynamic Discovery Option, the only configuration file needed is a LISTENER.ORA for each listener. That file is created as part of the installation procedure. If you are using Oracle Names without the DDO option, you must configure using Oracle Network Manager.

SQL*Net Easy Configuration

SQL*Net Easy Configuration makes configuration quick and simple by automatically creating configuration files needed by the networking products. Use SQL*Net Easy Configuration if:

Oracle Network Manager

 Oracle Network Manager includes a graphical user interface that enables you to view the network in a:

Oracle Network Manager enables you to configure more complex features, such as ANO.

Simple and Complex Network Considerations

SQL*Net Easy Configuration is ideal for smaller networks, while Oracle Network Manager is suitable for larger, more complex networks. Consider your network layout when selecting a configuration tool. This decision is important because once you select a tool and configure with it, you cannot use the other tool.

Review the guidelines below before choosing either SQL*Net Easy Configuration or Oracle Network Manager:

Additionally, note which Oracle Protocol Adapters can be configured with SQL*Net Easy Configuration or Oracle Network Manager:
Oracle Protocol Adapter Use SQL*Net Easy Configuration Use Oracle Network Manager
TCP/IP yes yes
SPX yes yes
DECnet no yes
Named Pipes yes yes
NetBIOS yes yes
LU6.21 no yes
Bequeath yes no
  1. LU6.2 for Windows NT must be configured manually by editing the TNSNAMES.ORA and LISTENER.ORA files. See "Specifying LU6.2 Addresses."

Understanding the Configuration Files

Oracle Network Products use the following configuration files:
On Your Server On Your Client
LISTENER.ORA SQLNET.ORA
NAMES.ORA TNSNAMES.ORA
SQLNET.ORA TNSNAV.ORA
TNSNAMES.ORA

Below is a description of the configuration files:
Configuration File Description
LISTENER.ORA

 Includes service names (or database aliases) and addresses of all listeners on a machine, the system IDs (SIDs) for the databases they listen for, and various control parameters used by the listener.
NAMES.ORA Contains control parameters for Oracle Names Servers that do not use the DDO. This file is not needed for the Dynamic Discovery Option.
SQLNET.ORA Includes optional diagnostic parameters, client information about Oracle Names Server, and can contain other optional parameters.
TNSNAMES.ORA Includes a list of service names (or databases aliases) of network databases mapped to connect descriptors.
TNSNAV.ORA Lists the local communities of the client profile or node. This file is not needed and used for single community networks. It is used only when working with MultiProtocol Interchange.

Additional Information: See Understanding SQL*Net for further information about this file.

Note
 On Window 3.x, a private version of TNSNAMES.ORA file can exist in the current working directory. For example, if you start SQL*Plus in ORAWIN\BIN, then SQL*Net looks for a local TNSNAMES.ORA in ORAWIN\BIN. If you start SQL*Plus in \PLUS, then SQL*Net looks for a local TNSNAMES.ORA in \PLUS. A consequence of this is that you can have multiple local TNSNAMES.ORA files in the various directories from which you start applications. In most cases, it is recommended from that only one TNSNAMES.ORA files exists in the ORACLE_HOME\NETWORK\ADMIN directory.

For samples and detailed descriptions of these files, see "Configuration Files."

A description of how the files are created is described below:
This File... Is...
LISTENER.ORA created during installation
NAMES.ORA created on the server from the Oracle Network Manager when configuring without the Dynamic Discovery Option
SQLNET.ORA created during installation on the clients and the server, and regenerated on the client from SQL*Net Easy Configuration or Oracle Network Manager
TNSNAMES.ORA created on clients and the server from SQL*Net Easy Configuration or Oracle Network Manager
TNSNAV.ORA created on clients and the server from Oracle Network Manager

Configuring a Network Without Oracle Names

After you have installed the necessary Oracle network products, use SQL*Net Easy Configuration or Oracle Network Manager to create the TNSNAMES.ORA and regenerate SQLNET.ORA configuration files.

This section describes how to use both these products.

Using SQL*Net Easy Configuration
caution
 SQL*Net Easy Configuration is mainly implemented by the Oracle Installer. Therefore, it cannot perform extensive error checking on the data you enter. Ensure that you enter the correct data.

SQL*Net Easy Configuration must be used on the server and each of the clients to create the SQLNET.ORA and TNSNAMES.ORA configuration files.
Note:
 If you are not authorized to use the server, ask a server administrator to help you.

To create the configuration files:

  1. From the server or client machine, start the SQL*Net Easy Configuration application:

    The SQL*Net Easy Configuration dialog box appears:

  2. Select Add Database Alias and choose OK.

    The Choose Database Alias dialog box appears:

  3. Enter a database alias name to identify the database to access and choose OK. The alias can be any name you choose.

    The Choose Protocol dialog box appears if more than one Oracle Protocol Adapter resides in your ORACLE_HOME directory.

    .

    Continue to Step 4. If you installed only one protocol adapter, the dialog box appropriate for your protocol adapter appears, as shown in Step 4. Skip to Step 5.

  4. Select the protocol to use for your database alias name and choose OK.

    The dialog box appropriate for your protocol adapter appears; the example here TCP/IP is assumed:

  5. Enter the appropriate information for your chosen protocol adapter in the first field and enter the name for the System ID (SID) of the database to which you want to connect in the Database Instance field. The database instance is typically ORCL.

  6. Choose OK.

    The Confirm Adding Database Alias dialog box appears:

  7. Choose Yes to confirm.

    The SQL*Net Easy Configuration dialog box re-appears.

    The configuration files are created in the ORACLE_HOME\NETWORK\ADMIN directory.
    Note
     You can add up to 15 new database aliases with SQL*Net Easy Configuration.

    The table below describes the results of installing SQL*Net Server and Client and adding a database alias with SQL*Net Easy Configuration:
    Action Result
    Install SQL*Net Server and SQL*Net Client SQLNET.ORA and LISTENER.ORA files are created on the server, and SQLNET.ORA is created on the client.
    Run SQL*Net Easy Configuration on the client SQLNET.ORA is regenerated and TNSNAMES.ORA is created on the client. If a previous TNSNAMES.ORA file was created, it is moved to TNSNAMES.001.
    Run SQL*Net Easy Configuration again on the client

    		 SQL*Net Easy Configuration creates a new TNSNAMES.ORA file, and the older TNSNAMES.ORA is moved to TNSNAMES.OLD.
    Note
     On Windows NT/95, pre-existing versions of the LISTENER.ORA and SQLNET.ORA files are incrementally backed up to LISTENER.001, LISTENER.002, SQLNET.001, SQLNET.002, and so on each time you run SQL*Net Server installation. This backup prevents these files from being overwritten.

  8. Select Exit SQL*Net Easy Configuration and choose OK.

  9. Continue to "Testing the Configuration on the Server" in this chapter.

Using Other SQL*Net Easy Configuration Features

 This section describes SQL*Net Easy Configuration's other features that allow you to:

Modifying a Database Alias

  1. From the server or client machine, start the SQL*Net Easy Configuration application:

    The SQL*Net Easy Configuration dialog box appears

  2. Select Modify Database Alias and choose OK.

    The Modify Database Alias dialog box appears with the list of database aliases (if any).

  3. Select the database alias to modify and choose OK.

    The Choose Protocol dialog box appears if you installed more than one Oracle protocol adapter. If not, the Enter Modification Information dialog box appears and you must go to Step 5.

  4. Select the protocol to use for your database alias name and choose OK.

    The Enter Modification Information dialog box appears.

  5. Accept the database alias or enter the appropriate database alias in the Database Alias field that corresponds to one of the following:

  6. Accept the database instance name or enter the SID of the database in the Database Instance field and choose OK.
    Note
     If you used SQL*Net version 1 in the past, you can use the same values for Service Name and Database Instance (SID). If you do not know this information, ask the person who administers your network or remote database.

    The Confirm Modifying Database Alias dialog box appears.

  7. Choose Yes to modify the Database Alias.

    The configuration files for your machine are modified with your edits.

    The SQL*Net Easy Configuration dialog box re-appears.

  8. Select Exit SQL*Net Easy Configuration and choose OK to exit from SQL*Net Easy Configuration.

Deleting a Database Alias

  1. From the server or client machine, start the SQL*Net Easy Configuration application:

  2. Select Delete Database Alias from the SQL*Net Easy Configuration dialog box and choose OK.

    The Delete Database Alias dialog box appears with the list of database aliases.

  3. Select the Database Alias to delete and choose OK.

    The Confirm Deleting Database Alias dialog box appears with the configuration information for that Database Alias.

  4. Select Yes to delete that Database Alias.

    The database alias is deleted from the configuration files for the machine you are on.

    The SQL*Net Easy Configuration dialog box re-appears.

  5. Select Exit SQL*Net Easy Configuration and choose OK to exit from SQL*Net Easy Configuration.

Viewing Configuration Information

  1. From the server or client machine, start the SQL*Net Easy Configuration application:

  2. Select View Configuration Information from the SQL*Net Easy Configuration dialog box and choose OK.

  3. The Choose Database Alias dialog appears with a list of databases.

  4. Select the database alias to view and choose OK.

    The Configuration Information dialog box appears with the configuration data for that database alias.

  5. View the information and choose OK.

    The SQL*Net Easy Configuration dialog box re-appears.

  6. Select Exit SQL*Net Easy Configuration and choose OK to exit from SQL*Net Easy Configuration.

Using Oracle Network Manager
Note
 Oracle Network Manager is a 16-bit application that can be run on Windows, Windows NT, and Windows 95. This application must be installed using the Windows installer and not the SETUP.EXE file located at the root of the CD.

This section describes how to use Oracle Network Manager to create the network configuration files.

When using Oracle Network Manager, you:

  1. Create a network definition.

  2. Save the network definition to a file or database.
    Note
     If you want to copy the client files to a Windows workstation, either comment out (REM)--or set to the value of OFF--the AUTOMATIC_IPC=ON statement in the SQLNET.ORA file. This prevents a client machine from trying to make a connection through IPC first before trying to use the protocol defined in the TNSNAMES.ORA file.

  3. Generate the network configuration files.

  4. Distribute the network configuration files to the server and each of the client machines.

Creating Configuration Files

 A basic configuration for a TCP/IP network not using Oracle Names is described below.
Additional Information
 See the Oracle Network Manager Administrator's Guide for complete information on all configuration steps described below.

To use Oracle Network Manager:

  1. Start Oracle Network Manager from the Oracle for Windows program group or go to ORAWIN\BIN\NETMAN.EXE from File Manager.

    The Oracle Network Manager appears with the Open Network Definition dialog box.

  2. Choose Cancel.

  3. Choose New from the File drop-down menu in the Oracle Network Manager menu bar, or choose the New icon from the Command Tool Bar.

    You are asked if you want to have a configuration walk-through. If you choose Yes, on-screen instructions appear on how to use Oracle Network Manager.

    If you choose No, continue to Step 4.

  4. Choose the Community icon or choose Community from the Create menu to bring up a property sheet for a new community. Use this property sheet to provide information about the protocol (or network community) the clients and servers share.

    In the General page of the Community property sheet:

    a. Enter TCP for name of the community in the Name field.

    b. Choose the TCP/IP protocol from the Protocol drop-down list.

    c. Choose OK to close the property sheet.

    TCP.world (the new community) is added to the Treeview.

  5. Choose the Node icon or choose Node from the Create menu to bring up a property sheet for a new node. Use this property sheet to provide information about the node on which the Oracle server is installed.

    In the Node property sheet:

    a. Enter the name of your Windows NT server in the Name field. If you are unsure of the name of your computer, go to the Control Panel and choose the Network icon. It displays a Network dialog that displays the name of your computer.

    b. Select User Defined for the NT operating system from the Type drop-down list.

    c. Choose the Communities tab, then choose the TCP.world community and choose << Add to add it the Selected list.

    d. Click OK to close the page and place the node on the Treeview community.

  6. Choose the listener icon or choose Listener from the Create menu to bring up a property sheet for a new listener. Use this property sheet to provide information about the listener for the Oracle7 server.

    In the Listener property sheet:

    a. The default name LISTENER appears; you do not need to change it unless there is more than one listener for the server. If there are multiple listeners for a server, each listener must have a unique name.

    b. If only one node has been defined, it appears in the Node field; you do not need to change it.

    c. If more than one has been defined, select the down arrow and select the desired node from the drop-down list box that appears.

    d. Choose the Addresses tab and choose Create. A Service Address property sheet appears in which to define the protocol-specific address of the listener, but do not make any changes, unless you want to change the host to the IP address of the Windows NT or the port number from the default.

    e. Choose OK to close the Service Address property sheet. A short form of the new address displays on the Addresses page.

    f. Choose OK to exit the Listener property sheet.

  7. Choose the Database icon or choose Database from the Create menu to bring up a property sheet for an Oracle7 database.

    In the Oracle Database property sheet:

    a. Enter the name of the database you want to use in the Name field. This is going to be your SQL*Net connect string. In most cases you use your SID name if you have multiple SIDs on your database, or your computer name for systems that have one database name.

    b. Enter the name of the database in the SID field. The default database name is ORCL.

    c. Choose OK to exit from the Oracle Database property sheet.

  8. Choose Validate from the File menu of the Oracle Network Manager window to verify that the information you entered is consistent and complete.

  9. Save the data you have entered into a network definition file by selecting Save from the File menu.

    The Save Network Definition dialog box displays the option to save the definition to the file system as a default choice.

    a. Choose OK. The Save As dialog appears, prompting you for a file name.

    b. Enter any name (this example uses GEN) and choose OK.

  10. Choose Generate from the File menu or choose the Generate icon from the Command Tool Bar to create the configuration files for your network.

    a. From the Export Network Definition dialog box that appears, choose File System. The Select a directory dialog box appears.

    b. Select the ADMIN directory to save the network configuration files to C:\ORAWIN\NETWORK\ADMIN and choose OK.

    The configuration files are created.

  11. Choose Exit from the File menu.

Results of Oracle Network Manager

 After creating the configuration files with Oracle Network Manager, the C:\ORAWIN\NETWORK\ADMIN\GEN directory contains two subdirectories:

The following configuration files exist where host_name is the name of the Oracle7 Server that you entered in Step 5.a.:
Server host_name contents TCP_WORL contents
SQLNET.ORA SQLNET.ORA
TNSNAMES.ORA TNSNAMES.ORA
TNSNAV.ORA TNSNAV.ORA
LISTENER.ORA

Distributing Configuration Files

The generated server configuration files need to distributed to ORACLE_HOME\NETWORK\ADMIN on the server, and the client configuration files need to distributed to \ORACLE_HOME\NETWORK\ADMIN on all clients.

See Chapter 6, "Distributing the Configuration Files," in the Oracle Network Manager Administrator's Guide for complete information on the various distribution methods, including FTP and NETFETCH.

Configuring a Network With Oracle Names

SQL*Net requires minimal configuration (TCP/IP, SPX and Named Pipes networks only) through Oracle Names. SQL*Net minimizes configuration by having:

Oracle Names Server configuration does not require a TNSNAMES.ORA on the clients. Additionally, if the DDO is used, SQLNET.ORA is not required on the clients.
Additional Information
 See:

Choosing Whether to Use Oracle Names and the Dynamic Discovery Option

 Oracle Names contains an option that provides dynamic registration of servers with well-known Names Servers on the network and automatic replication of data between Names Servers. If you use Oracle Names to provide a naming service for your network, you must decide whether to use the DDO.

If you choose to use the DDO in your network, you do not have to use Oracle Network Manager to create configuration files. If you are using SQL*Net for the first time, and are willing to accept all default parameters, with the Dynamic Discovery Option, the only configuration file needed is a LISTENER.ORA for each listener. That file is created as part of the installation process.

The DDO in Oracle Names 2.0 is not for every network. There are several factors o consider before using DDO on your network.

To configure an Oracle Names Server:
Note:
 The instructions below describe basic configuration steps for Oracle Names Servers. For complete instructions, see the Oracle Names Administrator's Guide.

  1. Ensure the listener is not running. Enter:

    LSNRCTL
    LSNRCTL>STATUS [listener_name]
     where listener_name is the name of the listener defined in the LISTENER.ORA file. It is not necessary to identify the listener if you are using the default listener, named LISTENER.

    If the STATUS command indicates the listener is running, continue to Step 2. If the listener is not running, skip to Step 3.

  2. Stop the listener. Enter:

    LSNRCTL>SET PASSWORD password
    LSNRCTL>STOP [listener_name]
     SET PASSWORD is only required if the password is set in the LISTENER.ORA file. The password defaults to ORACLE.

  3. Exit from the LSNRCTL utility. Enter:

    LSNRCTL>QUIT
  4. Ensure your network administrator has configured an alias for the installed Oracle Names Server in the Domain Name Server (DNS) with one of the following well-known names:
    The well-known host names for TCP connections The well-known computer Names for Named Pipes connections The well-known service name for an SPX connection
    ORANAMESRVR0
    ORANAMESRVR1
    ORANAMESRVR2
    ORANAMESRVR3
    ORANAMESRVR4     		ORANAMESRVR0
    ORANAMESRVR1
    ORANAMESRVR2
    ORANAMESRVR3
    ORANAMESRVR4     		ORANAMESRVR0
    Note
     The number 0 to 4 indicates the order in which the client tries to contact to the Oracle Names Servers, starting with ORANAMESRVR0.

    If you are using the DDO, skip to Step 6. If you are not using the DDO, continue to Step 5.

  5. Use Oracle Network Manager to:

    a. Create a network definition using Network Manager property sheets.

    b. Generate network component configuration files using the GENERATE command in Oracle Network Manager.

    c. Distribute the configuration files to the appropriate nodes on the network.
    Additional Information
     These procedures are all described in detail in the Oracle Network Manager Administrator's Guide.

    Configuration is complete. Skip to Step 8.

  6. On every client and the server, edit the NAMES.DIRECTORY_PATH parameter so it points to ONAMES in the SQLNET.ORA file:

    NAMES.DIRECTORY_PATH = (ONAMES, TNSNAMES)
  7. On every client and server, ensure the following line is in the SQLNET.ORA file:

    AUTOMATIC_IPC = OFF
  8. Comment out all ADDRESSes (including IPC) that you are not using in the LISTENER.ORA. For example:

      (ADDRESS_LIST =
    #        (ADDRESS=
     
    #          (PROTOCOL= IPC)
     
    #          (KEY= oracle.world)
     
    #        )
     
    #        (ADDRESS=
     
    #          (PROTOCOL= IPC)
     
    #          (KEY= ORCL)
     
    #        )
     
    #        (ADDRESS=
     
    #          (COMMUNITY= NMP.world)
     
    #          (PROTOCOL= NMP)
     
    #          (SERVER= hr-PC)
     
    #          (PIPE= ORAPIPE)
     
    #        )
     
            (ADDRESS= 
              (COMMUNITY= TCP.world)
     
              (PROTOCOL= TCP)
     
              (Port= 1521)
     
            )
     
            (ADDRESS= 
              (COMMUNITY= TCP.world)
     
              (PROTOCOL= TCP)
     
              (Port= 1526)
            )

      )
  9. Add the GLOBAL_DBNAME and USE_PLUG_AND_PLAY_listener_name (for DDO) parameters to the LISTENER.ORA file on the server: using a text editor:

    SID_LIST_listener_name=

       (SID_LIST =

          (SID_DESC =

             (SID_NAME = SID)

            (GLOBAL_DBNAME = global_dbname.domain)

          )

       )

    USE_PLUG_AND_PLAY_listener_name = ON
    USE_PLUG_AND_PLAY indicates to use the DDO and GLOBAL_DBNAME identifies the globally unique name for the database instance. Think of it as a database alias.

  10. Create and start the OracleNamesService by using the Names Control Utility, NAMESCTL. Enter:

    NAMESCTL
    NAMESCTL>START
     The OracleNamesService is created and configuration is complete.

  11. Continue to the next section, "Testing the Configuration on the Server."

Testing the Configuration on the Server

 Once you have configured the network, test the configuration by performing a loopback test on the server.

This section covers the following:

These instructions are valid for a network with or without an Oracle Names Server.

Setting Up for a Loopback Test

In order to perform a loopback test, the following must be performed prior to performing a loopback test:

  1. Starting Oracle Names (if not already started)

  2. Starting the Listener

Starting Oracle Names

 Command Line To start Oracle Names from the command line:

  1. Verify whether the Oracle Names Server is running or not running by using the Names Control Utility, NAMESCTL. Enter:

    NAMESCTL
    NAMESCTL>STATUS
     If the STATUS command indicates the Oracle Names Server is running, continue to Step 3. If the Oracle Names Server is not running, continue to Step 2.

  2. Start the Oracle Names Server. Enter:

    NAMESCTL>START
  3. Exit from the NAMESCTL utility. Enter:

    NAMESCTL>QUIT
Control Panel To start the Oracle Names Server from the Windows NT Control Panel's Services dialog box:

  1. Choose the Services icon in the Control Panel window.

    The Services dialog box appears.

  2. Look for the OracleNamesService.

    A blank in Status column indicates that the service is stopped.

    If the service is not running, continue to Step 3. Otherwise, skip to Step 4.

  3. Select the OracleNameService service and choose Start.

    The service is started.

  4. In the Services dialog box, choose the Close button.

Starting the Listener

 For SQL*Net to accept connections on the server, a listener must be started. If you have started an Oracle Names Server, the listener upon startup automatically register the databases specified in the SID_LIST_listener_name section of the LISTENER.ORA file with the well-know Oracle Names Servers.

Command Line To start the listener from the command line:

  1. Verify whether the listener is running or not running by using the Listener Control Utility, LSNRCTL. Enter:

    LSNRCTL
    LSNRCTL>STATUS [listener_name]
     where listener_name is the name of the listener defined in the LISTENER.ORA file. It is not necessary to identify the listener if you are using the default listener, named LISTENER.

    If the STATUS command indicates the listener is running, continue to Step 2. If the listener is not running, skip to Step 3.

  2. Even if the listener is running, it advised to stop and start it again. To stop the listener, enter:

    LSNRCTL>SET PASSWORD password
    LSNRCTL>STOP [listener_name]
     SET PASSWORD is only required if the password is set in the LISTENER.ORA file. The password defaults to ORACLE.

  3. Start the listener. Enter:

    LSNRCTL>START [listener_name]
  4. Exit from the LSNRCTL utility. Enter:

    LSNRCTL>QUIT
Control Panel To start the listener from the Windows NT Control Panel's Services dialog box:

  1. In the Control Panel window, choose the Services icon.

    The Services dialog box appears.

  2. Look for the OracleTNSListener service.

    A blank in Status column indicates that the service is stopped.

    If the listener is running, continue to Step 3. If the listener is running, skip to Step 4.

  3. Select the OracleTNSListener service and choose Start

    The service is started.

  4. In the Services dialog box, choose the Close button.

Performing a Loopback Test on the Server

 Once your network is configured and a SQL*Net network listener is started on an Oracle8 Server, clients connect to the Oracle8 Server using a SQL*Net service name (or database alias). The service name is mapped to the connect descriptor. Connect descriptors define protocol adapter information for the destination server's address and the system ID (SID) for the destination server.

This section show how to execute:

A loopback uses SQL*Net to go from the server right back to itself. Performing a successful loopback verifies that SQL*Net works on the server.
Note:
 In order to perform the loopback, ensure that the AUTOMATIC_IPC parameter is set to off ( AUTOMATIC_IPC=OFF) in the SQLNET.ORA file to turn off (Interprocess Communication) IPC. If it is left on, the loopback is performed through IPC instead of the connection going out of the network card with the protocol adapter, which defeats the purpose of the loopback test.

Loopback with Server Manager

To execute a loopback using Server Manager:

  1. Start Server Manager. Enter:

    SVRMGR23
    The SVRMGR> prompt appears:

  2. Connect to the database. Enter:

    SVRMGR>CONNECT SYSTEM/MANAGER@service_name
    or

    SVRMGR>CONNECT SYSTEM/MANAGER@global_dbname
    The service_name is the database alias you defined earlier with SQL*Net Easy Configuration or the Oracle Network Manager and the global_dbname is the global database name you defined in the LISTENER.ORA for the Oracle Names Server.

    Server Manager returns the following message:

    You probably do not have to use the full service name. There are two parameters in the SQLNET.ORA file which, if set, automatically adds domains to any connect string you use. These parameters are NAMES.DEFAULT_DOMAIN and NAME.DEFAULT_ZONE.

    For example, if your service name in the TNSNAMES.ORA file reads ORACLE.WORLD and the two .DEFAULT parameters are set to WORLD in the SQLNET.ORA file, the command to do a loopback is:

    SVRMGR> CONNECT SYSTEM/MANAGER@oracle
    The two parameters in SQLNET.ORA add a .WORLD extension to ORACLE, which matches the ORACLE.WORLD defined in the TNSNAMES.ORA file.

  3. Issue SQL commands.

  4. When done, enter:

    SVRMGR>EXIT
    Exiting Server Manager closes the database connection.

  5. Continue to the section, "Testing the Configuration on the Client."

Loopback with SQL*Plus

 To execute a loopback using SQL*Plus :

  1. Start the SQL*Plus application:

    A Log On dialog box appears:

  2. Enter SYSTEM in the User Name field, MANAGER in the Password field, and the database alias (from the TNSNAMES.ORA file) or the global database name for the Oracle Names Server (from the LISTENER.ORA file) in the Host String field.

  3. Choose OK.

    The Oracle SQL*Plus window appears with a SQL> prompt.

  4. Issue SQL commands.

  5. When done, enter:

    SQL>EXIT
    Exiting SQL*Plus closes the database connection.

  6. Continue to the next section, "Testing the Configuration on the Client."

Testing the Configuration on the Client

 After performing a loopback test, follow the procedures in this section:

Verifying TCP/IP Network Connections

 If your are using TCP/IP, follow the instructions below to specify the destination address for TCP/IP and use PING to see if the server is running.

Most TCP/IP transports attempt to use the DNS. DNS is a machine used to translate the host name specified in the TNSNAMES.ORA file into the host internet address (IP). If a Domain Name Server is present on your network and the TCP/IP vendor supports DNS, the host name is successfully translated to the host address. The host IP address can be determined by using the Control Panel's Network utility to access DNS information.

Depending on your vendor, workstation configuration, and network configuration, your TCP/IP software can also use a HOSTS file to map host names to Internet addresses if DNS is not detected or supported.

If DNS and the HOSTS file are unable to resolve the host name during a remote database connection, the following error message appears:

If your network administrator cannot resolve the problem, the solution to this error message is go around DNS and the HOSTS file by modifying the (HOST = server_name) section of the TNSNAMES.ORA so server_name is changed to the IP address of the server.

The following sections explain how to determine the server's IP address and verify that DNS and the HOSTS file are working correctly.

Determining the Server's IP Address

If you are not using TCP/IP, skip to "Verifying Oracle Database Connections Using TNSPING" in this chapter.

The instructions below explain how to determine the IP address from Windows NT 4.0. The instructions are different on Windows NT 3.51. Please see your operating system documentation for specific DNS information.

To determine the server's TCP/IP internet address:
Note
 If you are not authorized for access on the server, ask your server administrator for assistance.

  1. In the Control Panel window, choose the Network icon.

    The Network window appears.

  2. Choose the Protocols tab.

    The Protocols view appears:

  3. From the Protocol view, select the TCP/IP Protocol adapter and choose Properties...

    The Microsoft TCP/IP Properties dialog box appears with the IP Address view:

  4. Obtain the IP address and choose Cancel to close the Microsoft TCP/IP Properties dialog box.

  5. Choose Cancel to close the Network window.

  6. Continue to the next section, "Using PING."

Using PING

If you are using TCP/IP, PING allows you to determine if DNS or the HOSTS file are correctly set up and your network operating system is functioning correctly.

To use PING:

  1. From the client, enter:

    PING server_name
    where server_name is the host name, alias, or Internet address of the server to which you are trying to connect. If your network in functioning correctly, the following message appears:

    Reply from server_name: bytes=nn time=nnms
    If there is a problem, this message appears:

    Request timed out
    Or:

    Reply from server_name: Destination host unreachable
    The following is a partial list of reasons why a host is inaccessible:

    If PING returns an error message, ask your network administrator to help you resolve the problem. If the problem is not resolved, and you attempt to make a SQL*Net connection, you may receive one of the following error messages:

  2. Continue to the next section, "Verifying Oracle Database Connections Using TNSPING."

Verifying Oracle Database Connections Using TNSPING

 Use the TNSPNING utility to determine whether or not you can reach the listener service. TNSPING, however, never actually connects with the listener. A socket is never created and opened. TNSPING just checks to make sure a listener is running on the server side.

When you connect to a listener using TNSPING, an estimate of the round trip time in milliseconds appears. If TNSPING fails, a network error message appears without the overhead of a database connection.

To use TNSPING:

From the client, enter:

TNSPING service_name count
where service_name is the database alias (or service name) and count is the number of times the program attempts to reach the server. count is optional.

The output looks like:

TNS Ping Utility for 32-bit Windows: Version 3.0.2.0.0 - Production on 12-DEC-
96 20:20:33



Copyright, 1996(c) Oracle Corporation 1995. All rights reserved.





Attempting to contact 
(ADDRESS=(COMMUNITY=tcp.world)(PROTOCOL=TCP)(Host=server_name)(Port=1521))



OK (60 msec)




 Closing a Database Connection


Closing a database connection involves:




 Stopping Oracle Names


Stop the Oracle Names Server (if you are using it) when you have completed database connections.


 Command Line

To stop Oracle Names from the command line:


    


  1. Stop the Oracle Names Server by using the Names Control Utility, NAMESCTL. Enter:
    


    NAMESCTL
    


    NAMESCTL>STOP
    
    

  2. Exit from the NAMESCTL utility. Enter:
    


    NAMESCTL>QUIT
    



 Control Panel

To stop the Names Server from the Windows NT Control Panel's Services dialog box:


    


  1. Choose the Services icon in the Control Panel window.
    

The Services dialog box appears. 
    


  2. Look for the OracleNameService service. 
    


  3. Select the OracleNameService service and choose Stop.
    

The service is stopped.
    


  4. In the Services dialog box, choose the Close button.
    




 Stopping the Listener


Stop the listener when all database connections have completed and the Oracle Names Server has been stopped. 






 Note:


The listener can be left running on the server, if you choose.













 Command Line

To stop the listener from the command line: 






 Note


If you are not authorized for access on the server, ask your server administrator for assistance.














    


  1. Stop the listener from the Listener Control Utility, LSNRCTL. Enter:, 
    


    LSNRCTL
    


    LSNRCTL>SET PASSWORD password
    
    

    LSNRCTL>STOP [listener_name]
    
    
where listener_name is the name of the listener defined in the LISTENER.ORA file. It is not necessary to identify the listener if you are using the default listener, named LISTENER.
    

SET PASSWORD is only required if the password is set in the LISTENER.ORA file. The password is defaulted to ORACLE.
    


  2. Exit from the LSNRCTL utility. Enter:
    


    LSNRCTL>QUIT
    



 Control Panel

To stop the listener from the Windows NT Control Panel's Services dialog box: 


    


  1. Choose the Services icon in the Control Panel window.
    

The Services dialog box appears. 
    


  2. Look for the OracleTNSListener service.
    


  3. Select the OracleTNSListener service and choose Stop.
    

The Services confirmation dialog box confirms it is OK to stop the Service.
    


  4. Choose Yes.
    

The listener is stopped. 
    


  5. Choose the Close button in the Services dialog box.
    











































Oracle Network Products Getting Started for Windows Platforms
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Index