13.6.2 About Oracle Net Services for Oracle Heterogeneous Services

Heterogeneous Services is an integrated component within the Oracle database server, and provides the generic technology for accessing third-party systems from the Oracle database server. Heterogeneous Services enables you to:

• Use Oracle SQL to transparently access data stored in third-party systems as if the data resides within an Oracle database server.

• Use Oracle procedure calls to transparently access third-party systems, services, or application programming interfaces (APIs) from your Oracle distributed environment.

While Heterogeneous Services provides the generic technology in the Oracle database server, a Heterogeneous Services agent is required to access a particular third-party system.

• Configuring Oracle Database to Connect to Agents
  To initiate a connection to the third-party system, the Oracle database server starts an agent process through the listener on the gateway.

13.6.2.1 Configuring Oracle Database to Connect to Agents

To initiate a connection to the third-party system, the Oracle database server starts an agent process through the listener on the gateway.

The following procedure describes how to configure the Oracle database server to be able to connect to the agents:

1. Configure the listener on the gateway to listen for incoming requests from the Oracle database server and spawn Heterogeneous Services agents by configuring the following parameters in the listener.ora file:

   • PROGRAM: The name of the agent executable

   • ORACLE_HOME: The Oracle home location of the agent executable

   • SID_NAME: The Oracle system identifier (SID)

2. Configure the PROGRAM, ORACLE_HOME, and SID parameters in Oracle Enterprise Manager Cloud Control.

   1. Access the Net Services Administration page in Oracle Enterprise Manager Cloud Control.

      See Using Oracle Enterprise Manager Cloud Control to Configure Oracle Net Services.

   2. Select Listeners from the Administer list, and then select the Oracle home that contains the location of the configuration files.

   3. Click Go.

      The Listeners page appears.

   4. Select the listener created by Oracle Net Configuration Assistant, and then click Edit.

      The Edit Listeners page appears.

   5. Click the Other Services tab.

   6. Click Add.

      The Create Other Service page appears.

   7. Enter the program name in the Program Name field that will be run to create a gateway, the Oracle home where the agent executable resides in the Oracle Home Directory field, and the Oracle System Identifier (SID) or service name of the third-party system in the SID field.

   8. Click OK.

      The Edit Listener page appears.

   9. Click OK to modify the listener.

      The Listeners page appears.

      The listener.ora file updates information about the Heterogeneous Services, as shown in the following:

      SID_LIST_LISTENER=
       (SID_LIST=
        (SID_DESC=
         (SID_NAME=sybasegw)
         (ORACLE_HOME=/oracle12c)
         (PROGRAM=tg4sybs)))
      

3. On the computer where the Oracle database resides, set up a network service name to connect to the listener on the gateway. The connect descriptor must include the HS=ok clause to ensure the connection uses Heterogeneous Services, as follows:

   1. Create a network service name that can be used for connections from the Oracle database server to a third-party system.

      See Task 1, "Configure Net Services Names" for local naming instructions and Create Net Service Names in the Directory for directory naming instructions.

   2. Use either Oracle Enterprise Manager Cloud Control or Oracle Net Manager to configure HS=ok.

      • For Oracle Enterprise Manager Cloud Control, access the Net Services Administration page, select Local Naming for the listener, and then click the Advanced tab in the Create Net Service Name page. Next, click Use for Heterogeneous Services.

      • For Oracle Net Manager, click Advanced in the Service Identification box. The Advanced Service Options dialog box appears. Click Use for Heterogeneous Services.

   3. Click OK to confirm the change.

      The tnsnames.ora file updates with the new network service name configured for Heterogeneous Services, as shown in the following:

      sybase_gtw=
       (DESCRIPTION=
        (ADDRESS=(PROTOCOL=tcp)(HOST=gate-server)(PORT=1521))
        (CONNECT_DATA=
          (SERVICE_NAME=sybasegw)
        )
          (HS=ok)))
       )