8
Enabling Advanced Net8 Features

This chapter describes how to enable advanced features. It includes the following sections:

• Configuring Advanced Network Address and Connect Data Information

• Configuring Transparent Application Failover

• Configuring Client Attributes for Names Resolution

• Configuring Advanced Profile Information

• Configuring Preferred Oracle Names Servers

• Configuring Oracle Connection Manager Features

• Configuring Connections to Non-Oracle Database Services

Configuring Advanced Network Address and Connect Data Information

This section contains the following advanced connect descriptor topics:

• Creating a List of Listener Protocol Addresses

• Configuring Address List Parameters

• Configuring Advanced Connect Data Parameters

Creating a List of Listener Protocol Addresses

A database service may be accessed by more than one network route, or listener address. In the following example, sales.us.acme.com can connect to sales.us.acme.com using listeners on either sales1-server or sales2-server.

sales.us.acme.com=
 (description=
  (address_list=
    (address=(protocol=tcp)(host=sales1-server)(port=1521))
    (address=(protocol=tcp)(host=sales2-server)(port=1521)))
  (connect_data=
    (service_name=sales.us.acme.com)))

To add a network protocol address to an existing net service name or database service:

1. Start Net8 Assistant:
   • On UNIX, run netasst from $ORACLE_HOME/bin.

   • On Windows NT, choose Start > Programs > Oracle - HOME_NAME > Network Administration > Net8 Assistant.

2. In the navigator pane, expand Directory or Local > Service Naming.

3. Select either a net service name or a database service.

   The right pane displays the current destination service and address list.

4. In the Address Configuration box, click "+".

   A new address tab appears:

   
   
5. Select the protocol and enter appropriate address information.

   See Also: Appendix B for details about protocol address parameters

6. Order the protocol addresses according to where they should be in the address list with the left-arrow and right-arrow buttons. Unless multiple address options are configured, the first address in the list is contacted.

   See Also: "Configuring Address List Parameters" for address list options

7. Click Apply.

Configuring Address List Parameters

When a database service is accessible by multiple listener protocol addresses, it is important to specify the order of how the addresses are to be used. For example, the addresses can be chosen randomly or tried sequentially.

When multiple protocol addresses have been configured for a net service name or database service, the following options may be configured:

Parameter	Description
SOURCE_ROUTE (Source Routing	Instructs Net8 to use each address in the order presented until the destination reached when set to ON. This parameter is required when reaching the destination requires more than one address stop. This feature is typically used to enable Oracle Connection Manager features.
FAILOVER (Connect-Time Failover)	At connect time, instructs Net8 to fail over to a different listener if the first listener fails when set to ON. The number of addresses in the list determines how many addresses are tried. When set to OFF, instructs Net8 to try one address. Connect-time failover is turned ON by default for multiple address lists (ADDRESS_LIST), connect descriptors (DESCRIPTION), and multiple connect descriptors (DESCRIPTION_LIST). Important: Do not set the GLOBAL_DBNAME parameter in the SID_LIST_listener_name section of the listener.ora file. A statically configured global database name disables connect-time failover.
LOAD_BALANCE (Client Load Balancing)	When set to ON, instructs Net8 to progress through the list of listener addresses in a random sequence, balancing the load on the various listeners. When set to OFF, instructs Net8 to try the addresses sequentially until one succeeds. Client load balancing is turned ON by default for multiple connect descriptors (DESCRIPTION_LIST).

Implementation of these parameter depends on the naming method used. The following table describes the tools to configure connect-time failover or client load balancing. Source routing involves other configuration that goes beyond the scope of this section.

See Also: "Configuring Clients for Oracle Connection Manager" for more information about configuring clients for source routing

Naming Method	Tool to Configure Multiple Address Options
Local Naming	Net service names stored in a tnsnames.ora file may be configured for connect-time failover and client load balancing using Net8 Assistant. See the procedure that follows.
Directory Naming	Net service names and database services stored in a directory may be configured for connect-time failover and client load balancing using Net8 Assistant. See the procedure that follows.
Oracle Names	Net service names stored in an Oracle Names server may be configured for connect-time failover and client load balancing using the following tools: NAMESCTL REGISTER Net8 Assistant See Also: "Task 6: Register Data with the Oracle Names Server"

To configure connect-time failover or client load balancing:

1. Start Net8 Assistant:
   • On UNIX, run netasst from $ORACLE_HOME/bin.

   • On Windows NT, choose Start > Programs > Oracle - HOME_NAME > Network Administration > Net8 Assistant.

2. In the navigator pane, expand Directory or Local > Service Naming.

3. Select either a net service name or a database service.

   The right pane displays the current destination service and address list:

   
   
4. In the Address Configuration box, click Advanced.

   The Address List Options dialog box appears:

   
   

   The following table describes the options:

   Net8 Assistant Option	Parameter
   Try each address, in order, until one succeeds	FAILOVER=ON for release 8.1 clients SOURCE_ROUTE=OFF for pre-release 8.1 clients.
   Try each address, randomly, until one succeeds Note: This option is not enabled if "Use Options Compatible with Net8 8.0 Clients" is selected.	LOAD_BALANCE=ON FAILOVER=ON
   Try one address, selected at random Note: This option is not enabled if "Use Options Compatible with Net8 8.0 Clients" is selected.	LOAD_BALANCE=ON
   Use each address in order until destination reached	SOURCE_ROUTE=ON
   Use only the first address Note: This option is not enabled if "Use Options Compatible with Net8 8.0 Clients" is selected.	LOAD_BALANCE=OFF FAILOVER=OFF SOURCE_ROUTE=OFF

5. Select one of the address list options, then click OK.

6. In the right pane, click Apply.

In the following example, the tnsnames.ora file is configured for client load balancing with the "Try each address, randomly, until one succeeds" option:

sales.us.acme.com=
 (description=
  (address_list=
  (load_balance=on)
   (address=(protocol=tcp)(host=sales1-server)(port=1521)) 
   (address=(protocol=tcp)(host=sales2-server)(port=1521)))
  (connect_data=
    (service_name=sales.us.acme.com))) 

In the following example, the tnsnames.ora file is configured for connect-time failover with the "Try each address, in order, until one succeeds" option:

sales.us.acme.com=
 (description=
  (address_list=
   (load_balance=off)
   (failover=on)
   (address=(protocol=tcp)(host=sales1-server)(port=1521)) 
   (address=(protocol=tcp)(host=sales2-server)(port=1521)))
  (connect_data=(service_name=sales.us.acme.com)))

Configuring Advanced Connect Data Parameters

The connect data portion of a connect descriptor defines the destination database service. In the following example, SERVICE_NAME defines a service called sales.us.acme.com:

sales.us.acme.com=
 (description=
    (address=(protocol=tcp)(host=sales-server)(port=1521))
  (connect_data=
    (service_name=sales.us.acme.com)))

Besides the service name, connect data information may be optionally configured with the following parameters:

tnsnames.ora File Parameter	Net8 Assistant Field/Option	Description
INSTANCE_NAME	Instance Name	Identifies the database instance to access The instance name can be obtained from the INSTANCE_NAME parameter in the initialization parameter file. Note: Not enabled if "Use Oracle8i Release 8.0 Compatible Identification" is checked. See Also: "Understanding Connect Descriptors"
SDU	Session Data Unit Size	If you want to optimize the transfer rate of data packets being sent across the network, you can specify the session data unit (SDU) size to change the performance characteristics having to do with the packets sent across the network. See Also: "Adjusting the Session Data Unit (SDU) Size for Data Transfer Optimization"
HS	Use for Heterogeneous Services	If you want an Oracle8i server to access a non-Oracle system, turn this option on. See Also: "Configuring Net8 for Oracle Heterogeneous Services"
Oracle Rdb Settings
RDB_DATABASE)	Oracle RDB Database	Specifies the file name of an Oracle RDB database See Also: "Configuring Net8 for an Oracle Rdb Database"
TYPE_OF_SERVICE)	Type of Service	Specifies the type of service to use for an Oracle RDB database See Also: "Configuring Net8 for an Oracle Rdb Database"
GLOBAL_NAME)	Global Database Name	Identifies the Oracle Rdb database See Also: "Configuring Net8 for an Oracle Rdb Database"

Implementation of these parameter depends on the naming method used. The following table describes the tools to configure connect-time failover or client load balancing. Source routing involves other configuration that goes beyond the scope of this section.

See Also: "Configuring Clients for Oracle Connection Manager" for more information about configuring clients for source routing

Naming Method	Tool to Configure Multiple Address Options
Local Naming	Net service names stored in a tnsnames.ora file may be configured with advanced connect data information using Net8 Assistant. See the procedure that follows.
Directory Naming	Net service names and database services stored in a directory may be configured with advanced connect data information using Net8 Assistant. See the procedure that follows.
Oracle Names	Net service names and database services stored in an Oracle Names server may be configured with advanced connect data information using the following tools: NAMESCTL REGISTER Net8 Assistant See Also: See "Task 6: Register Data with the Oracle Names Server"

To configure advanced CONNECT_DATA parameters for either a net service name or a database service:

1. Start Net8 Assistant:
   • On UNIX, run netasst from $ORACLE_HOME/bin.

   • On Windows NT, choose Start > Programs > Oracle - HOME_NAME > Network Administration > Net8 Assistant.

   • Network Administration > Net8 Assistant.

2. In the navigator pane, expand Directory or Local > Service Naming.

3. Select either a net service name or a database service.

   The right pane displays the current destination service and address list:

   
   
4. In the Service Identification box, click Advanced.

   The Advanced Service Options dialog box appears:

   
   
5. Enter fields or select options as appropriate, then click OK.

6. In the right pane, click Apply.

Configuring Transparent Application Failover

Transparent application failover (TAF) instructs Net8 to fail over an established connection that has failed to a different listener. This enables the user to continue to work using the new connection as if the original connection had never failed.

TAF involves manual configuration of a net service name that includes the FAILOVER_MODE parameter included in the CONNECT_DATA portion of the connect descriptor.

This sections covers the following topics:

• FAILOVER_MODE Parameters

• TAF Implementation

• Verification

FAILOVER_MODE Parameters

The FAILOVER_MODE parameter must be included in the CONNECT_DATA portion of a connect descriptor. FAILOVER_MODE may contain the following parameters:

tnsnames.ora file Parameter	Description
BACKUP	Specifies a different net service name for backup connections. A backup should be specified when using PRECONNECT to pre-establish connections.
TYPE (Required)	Specifies the type of failover. Three types of Net8 failover functionality are available by default to Oracle Call Interface (OCI) applications: SESSION: Fails over the session; that is, if a user's connection is lost, a new session is automatically created for the user on the backup. This type of failover does not attempt to recover selects. SELECT: Enables users with open cursors to continue fetching on them after failure. However, this mode involves overhead on the client side in normal select operations. NONE: This is the default, in which no failover functionality is used. This can also be explicitly specified to prevent failover from happening.
METHOD	Determines how fast failover occurs from the primary node to the backup node: BASIC: Establishes connections at failover time. This option requires almost no work on the backup server until failover time. PRECONNECT: Pre-establishes connections. This provides faster failover but requires that the backup instance be able to support all connections from every supported instance.
RETRIES	Specifies the number of times to attempt to connect. If DELAY is specified, RETRIES defaults to five retry attempts.
DELAY	Specifies the amount of time in seconds to wait between connect attempts. If RETRIES is specified, DELAY defaults to one second.

TAF Implementation

Important: Do not set the GLOBAL_DBNAME parameter in the SID_LIST_listener_name section of the listener.ora. A statically configured global database name disables TAF.

Depending on the FAILOVER_MODE parameters, TAF can be implemented in a number of ways. Oracle recommends the following methods:

• Implementing TAF with Connect-Time Failover and Client Load Balancing

• Retrying a Connection

• Pre-Establishing a Connection

Implementing TAF with Connect-Time Failover and Client Load Balancing

TAF can be implemented with connect-time failover and client load balancing for multiple addresses. In the following example, Net8 connects randomly to one of the listener addresses on sales1-server or sales2-server. If the instance fails after the connection, Net8 fails over to the other node's listener, reserving any SELECT statements in progress.

sales.us.acme.com=
 (description=
  (load_balance=on) 
  (failover=on) 
  (address=
       (protocol=tcp)  
       (host=sales1-server)  
       (port=1521)) 
 (address=
       (protocol=tcp)  
       (host=sales2-server)  
       (port=1521)) 
  (connect_data=
     (service_name=sales.us.acme.com) 
     (failover_mode=
       (type=select) 
       (method=basic))))

Retrying a Connection

TAF also provides the ability to automatically retry connecting if the first connection attempt fails with the RETRIES and DELAY parameters. In the following example, Net8 tries to connect to the listener on sales1-server. If the connection attempt fails, Net8 waits 15 seconds before trying to connect again. Net8 attempts to connect up to 20 times.

sales.us.acme.com=
 (description=
  (address=
       (protocol=tcp)  
       (host=sales1-server)  
       (port=1521)) 
  (connect_data=
     (service_name=sales.us.acme.com) 
     (failover_mode=
       (type=select) 
       (method=basic)
       (retries=20)
       (delay=15))))

Pre-Establishing a Connection

A backup connection can be pre-established. The initial and backup connections must be explicitly specified. In the following example, Net8 connects to the listener on sales1-server. If sales1-server fails after the connection, Net8 fails over to sales2-server, reserving any SELECT statements in progress.

sales.acme.com=
 (description=
  (address=
       (protocol=tcp)  
       (host=sales1-server)  
       (port=1521)) 
  (connect_data=
     (service_name=sales.us.acme.com) 
     (instance_name=sales1) 
     (failover_mode=
       (backup=sales2.acme.com) 
       (type=select) 
       (method=preconnect))))
sales2.acme.com=
 (description=
  (address=
       (protocol=tcp)  
       (host=sales2-server)  
       (port=1521)) 
  (connect_data=
     (service_name=sales.us.acme.com) 
     (instance_name=sales2)))

Verification

You can query FAILOVER_TYPE, FAILOVER_METHOD, and FAILED_OVER columns in the V$SESSION view to verify that TAF is correctly configured.

See Also: Oracle8i Reference for more information about the V$SESSION view

Configuring Client Attributes for Names Resolution

The following sections describe available client configuration options:

• Configuring a Default Domain for Clients

• Prioritizing Naming Methods

• Routing Connection Requests

Configuring a Default Domain for Clients

In environments where the client often requests names from a specific domain, it is appropriate to set a default domain in the client's sqlnet.ora file with the NAMES.DEFAULT_DOMAIN parameter.

When a default domain is set, it is automatically appended to any unqualified net service name given in the connect string, and then compared to net service names stored in a tnsnames.ora file or Oracle Names server.

For example, if the client tnsnames.ora file contains a net service name of sales.us.acme.com, the user can enter the following connect string:

CONNECT scott/tiger@sales

In this example, sales gets searched as sales.us.acme.com.

If the connect string includes the domain extension, such as in CONNECT scott/tiger@sales.acme.com, the domain is not appended. If a net service name in a tnsnames.ora file or Oracle Names server is not domain qualified and this parameter is set, the net service name must be entered with a dot ("."). For example, if domain is set to us.acme.com and the client tnsnames.ora file contains a net service name of sales, the user would enter the following connect string:

CONNECT scott/tiger@sales.

Note: During installation, Net8 Configuration Assistant sets the default domain to your client's network domain.

To specify a default domain:

1. Start Net8 Assistant:
   • On UNIX, run netasst from $ORACLE_HOME/bin.

   • On Windows NT, choose Start > Programs > Oracle - HOME_NAME > Network Administration > Net8 Assistant.

2. In the navigator pane, expand Local > Profile.

3. From the list in the right pane, select Naming.

4. Click the Oracle Names tab:

   
   

5. In the Default Domain field, enter the domain.

6. Choose File > Save Network Configuration.

   The sqlnet.ora file should contain an entry that looks like the following:

   names.default_domain=com
   

Prioritizing Naming Methods

After naming methods are configured, as described in Chapter 6, they must be prioritized. The naming method at the top of the list is used first to resolve a net service name. If it cannot resolve the net service name, the second method in the list is used to resolve the net service name.

To specify the order of naming methods:

1. Start Net8 Assistant:
   • On UNIX, run netasst from $ORACLE_HOME/bin.

   • On Windows NT, choose Start > Programs > Oracle - HOME_NAME > Network Administration > Net8 Assistant.

2. In the navigator pane, expand Local > Profile.

3. From the list in the right pane, select Naming.

4. Click the Methods tab:

   
   

   Available naming methods are described in the following table:

   Naming Method	Description
   TNSNAMES	Local Naming Net service names are resolved using the tnsnames.ora file which resides on the client.
   LDAP	Directory Naming Net service names and database service names are resolved through a directory server.
   ONAMES	Oracle Names Net service names and database service names are resolved centrally, through an Oracle Names server.
   HOSTNAME	Host Naming Net service names are resolved using the host naming method. Certain criteria must be met to use host naming. See Also: "Configuring the Host Naming Method"
   CDS	Cell Directory Services This naming method is available with Oracle Advanced Security option. See Also: Oracle Advanced Security Administrator's Guide
   NDS	Novell Directory Services (NDS)
   NIS	Network Information Service (NIS)

5. Choose from the Available Methods list which naming method you want to use.

6. Select naming methods from the Available Methods list, then click the right-arrow button.

   The naming method moves to the Selected Methods list.

7. Order the naming methods according to the order in which you want Net8 to try to resolve the net service name or database service name. Select a naming method in the Selected Methods list, and click Promote or Demote to move the selection up or down in the list.

8. Choose File > Save Network Configuration.

   The sqlnet.ora file updates with the NAMES.DIRECTORY_PATH parameter:

   names.directory_path=(onames, tnsnames)
   

Routing Connection Requests

Clients and servers acting as clients can be configured so connection requests are directed to a specific process at all times. The sqlnet.ora file parameters described in the following table can be used to route connection requests:

sqlnet.ora File Parameter	Net8 Assistant Option	Description
USE_DEDICATED_SERVER	Always Use Dedicated Server	Forces the listener to spawn a dedicated server for all network session from this client. It does this by adding (SERVER=DEDICATED) to the CONNECT_DATA portion of connect descriptors. This way, connections from this client use dedicated servers, even if multi-threaded server (MTS) is configured.
USE_CMAN	Prefer Connection Manager Routing	Instructs the client to an Oracle Connection Manager whenever possible. If no Oracle Connection Manager addresses are available, connections are routed through any available listener address. Note: If you are using Oracle Connection Manager with Oracle Names, this option must be set on clients and Oracle Names servers.

To route connection requests:

1. Start Net8 Assistant:
   • On UNIX, run netasst from $ORACLE_HOME/bin.

   • On Windows NT, choose Start > Programs > Oracle - HOME_NAME > Network Administration > Net8 Assistant.

2. In the navigator pane, expand Local > Profile.

3. From the list in the right pane, select General.

4. Click the Routing tab:

   
   

5. Click the preferred way you want connection requests routed.

6. Choose File > Save Network Configuration.

Configuring Advanced Profile Information

The sqlnet.ora file can be configured with the following advanced parameters:

sqlnet.ora File Parameter	Net8 Assistant Field/Option	Description
SQLNET.EXPIRE_TIME	TNS Time Out Value	This option can be used only on the server. Sets a dead connection time-out value. Net8 sends a probe periodically to verify that a client-server connection is still active. This ensures that connections are not left open indefinitely, due to an abnormal client termination. If the probe finds a dead connection, or a connection that is no longer in use, it returns an error, causing the server process to exit. Limitations on using the dead connection detection feature are: Dead connection detection is not allowed on bequeathed connections. Though very small, a probe packet generates additional traffic that may downgrade network performance. The server may need to perform additional processing to distinguish the connection probing event from other events that occur, depending on which operating system is in use. This may also result in downgrading network performance.
SQLNET.CLIENT_REGISTRATION	Client Registration ID	Sets a unique identifier for this client machine. This identifier is passed to the listener with any connection request. The identifier can be any string up to 128 characters long.
BEQUEATH_DETACH	Turn Off UNIX Signal Handling	Since the client application spawns a server process internally through the Bequeath protocol as a child process, the client application becomes responsible for cleaning up the child process when it completes. When the server process completes its connection responsibilities, it becomes a defunct process. Signal handlers are responsible for cleaning up these defunct processes. Setting this parameter configures the client profile to pass this process to the UNIX init process by disabling signal handlers.
DISABLE_OOB	Disable Out-of-Band Break	If deselected or turned OFF, enables Net8 to send and receive "break" messages using urgent data provided by the underlying protocol. If selected or turned ON, disables the ability to send and receive "break" messages using urgent data provided by the underlying protocol. Once enabled, this feature applies to all protocols used by this client. See Also: Oracle operating-system documentation to determine if the protocols you are using supports urgent data requests. TCP/IP is an example of a protocol that supports this feature.

To set advanced features for clients:

1. Start Net8 Assistant:
   • On UNIX, run netasst from $ORACLE_HOME/bin.

   • On Windows NT, choose Start > Programs > Oracle - HOME_NAME > Network Administration > Net8 Assistant.

2. In the navigator pane, expand Local > Profile.

3. From the list in the right pane, select General.

4. Click the Advanced tab:

   
   

5. Enter the values for the option(s) you would like to set.

6. Choose File > Save Network Configuration.

Configuring Preferred Oracle Names Servers

If you are using Oracle Names as a naming method, you can specify the name and address of preferred Oracle Names servers to take precedence over any other available Oracle Names server addresses. Net8 routes name resolution requests to each preferred Oracle Names Server until a response is received.

Preferred Oracle Names servers are an alternative to using the Discover Oracle Names Servers command in Net8 Assistant or the REORDER_NS command in the NAMESCTL control utility. These commands create a list of Oracle Names servers based on what is available throughout the network and ranks them in the order of fastest response time. Preferred Oracle Names servers override any other Oracle Names servers found during the discovery process. Once you have initially discovered an Oracle Names server, you may want to delete preferred Oracle Names servers.

See Also: "Differences Between Versions of Oracle Names" for a description of how Oracle Names server lists are created "Task 4: Configure Clients and Database Servers To Use Oracle Names Servers" for information about discovering Oracle Names servers

To specify a preferred Oracle Names server:

1. Start Net8 Assistant:
   • On UNIX, run netasst from $ORACLE_HOME/bin.

   • On Windows NT, choose Start > Programs > Oracle - HOME_NAME > Network Administration > Net8 Assistant.

2. In the navigator pane, expand Local > Profile.

3. From the list in the right pane, select Preferred Oracle Names Servers.

4. Click New:

   
   

5. Choose the protocol and enter the requested protocol address information for an Oracle Names server configured on that address.

   See Also: Appendix B for protocol parameter settings

6. Repeat Steps 4 and 5 for each additional Oracle Names server you want added to the list.

7. Choose File > Save Network Configuration.

   The sqlnet.ora file updates with the NAMES.PREFERRED_SERVERS parameter:

   names.preferred_servers=
     (address=(protocol=tcp) (host=namesrv1)(port=1575))
   

   Note: The preferred Oracle Names server(s) must match the Oracle Names listening protocol address(es) you configured in the names.ora file with the NAMES.ADDRESSES parameter.

Configuring Oracle Connection Manager Features

The following sections describe how to configure Oracle Connection Manager features:

• Enabling Connection Concentration

• Enabling Multi-Protocol Support

• Enabling Net8 Access Control

• Configuring Clients for Oracle Connection Manager

Enabling Connection Concentration

Oracle Connection Manager enables you to take advantage of the ability to multiplex or funnel multiple logical client network sessions through a single transport connection to a multi-threaded server destination. This is accomplished through Oracle Connection Manager's connection concentration feature.

To configure connection concentration, perform these tasks:

Task 1: Configure Oracle Connection Manager

Task 2: Configure the Server

Task 3: Configure Clients

Task 1: Configure Oracle Connection Manager

Oracle Connection Manager accepts client connection requests at the following default listening address:

cman=(address=(protocol=tcp)(host=anyhost)(port=1630))

Oracle Connection Manager also listens for local and remote administration commands at the following listening address:

cman_admin=(address=(protocol=tcp)(host=anyhost)(port=1830))

If you do not want to use the default addresses, you must create a cman.ora file with the following information:

cman=(address=(protocol_address_information))
cman_admin=(address=(protocol_address_information))

A cman.ora file should exist in $ORACLE_HOME/network/admin on UNIX and ORACLE_HOME\network\admin on Windows NT that you can edit.

See Also: "Oracle Connection Manager Parameters (cman.ora)" for more information about the cman.ora file Appendix B for more information about protocol syntax needed for address information

Note: Net8 Assistant does not support configuration of the cman.ora file, so changes must be made manually.

Task 2: Configure the Server

Verify that the destination server is configured with multi-threaded server (MTS) and that the multiplexing option is turned on. MTS and multiplexing may be turned on using Oracle Database Configuration Assistant or by setting the MTS_DISPATCHERS parameter in the initialization parameter file with the PROTOCOL and MULIPLEX attributes. For example:

mts_dispatchers="(protocol=tcp) (multiplex=on)"

Attribute	Description
PROTOCOL (PRO or PROT)	The network protocol (TCP in the example above) for which the dispatcher generates a listening end point.
MULTIPLEX (MUL or MULT)	Used to enable connection concentration. If 1, ON, YES, TRUE, or BOTH is specified, then connection concentration is enabled for both incoming and outgoing network connections. If IN is specified, the connection concentration is enabled for incoming network connections from the client. If OUT is specified, the connection concentration is enabled for outgoing network connections. If 0, NO, OFF, or FALSE is specified, then connection concentration is disabled for both incoming and outgoing network connections.

Task 3: Configure Clients

Client support is accomplished by creating two addresses, the first for the Oracle Connection Manager and the second for the listener. Configuration varies according to naming method, as described in the following table:

Naming Method	Procedure
Local Naming and Directory Naming	An address list must be created, where the first address must be for the Oracle Connection Manager, and the second address must be for the listener. In order to have the client connect to the Oracle Connection Manager first and have the Oracle Connection Manager then connect to the listener, the SOURCE_ROUTE parameter must be set. See Also: "Configuring Clients for Oracle Connection Manager" to configure the Oracle Connection Manager and listener addresses
Oracle Names	Oracle Names servers are automatically updated with the listener and Oracle Connection Manager addresses. In order for a client using an Oracle Names server to send requests to Oracle Connection Manager, the USE_CMAN=TRUE parameter must be set in the sqlnet.ora file on clients and machines where each Oracle Names server resides. To set this parameter, follow the procedure in "Routing Connection Requests".

Example 8-1 shows a comparison of a regular tnsnames.ora file and a tnsnames.ora file with an entry to use the Oracle Connection Manager (Oracle Connection Manager entries are shown in boldface text):

Example 8-1 tnsnames.ora File with and without Oracle Connection Manager

sales= (description= (address= (protocol=tcp) (host=sales-pc) (port=1521)) (connect_data= (service_name=sales,com)))

sales= (description= (source_route=yes) (address= (protocol=tcp) (host=cman-pc) (port=1630)) (address= (protocol=tcp) (host=sales-pc) (port=1521)) (connect_data= (service_name=sales.com)))

tnsnames.ora File Element	Description
source_route=yes	Creates a source route of addresses through an Oracle Connection Manager to the destination database
(address= (protocol=tcp) (host=cman-pc) (port=1630))	This first address is to the Oracle Connection Manager. From here, the Oracle Connection Manager connects to the database service through the listener

Enabling Multi-Protocol Support

Note: If more than one Oracle Connection Manager is used in the connection path, you cannot use Oracle Names to connect clients through it.

Oracle Connection Manager also provides multiple protocol support enabling a client and server with different networking protocols to communicate with each other. An Oracle Connection Manager can listen on any protocol that Oracle supports.

Without multi-protocol support, a client that uses SPX cannot connect to a server that uses TCP/IP. If Oracle Connection Manager is configured for TCP/IP, the client can connect to Oracle Connection Manager using SPX, and Oracle Connection Manager can connect to the server using TCP/IP.

To configure multi-protocol support, performs these tasks:

Task 1: Configure Oracle Connection Manager

Task 2: Configure Clients

Task 1: Configure Oracle Connection Manager

Oracle Connection Manager accepts client connection requests at the following default listening address, and:

cman=(address=(protocol=tcp)(host=anyhost)(port=1630))

listens for local and remote administration commands at the following listening address:

cman_admin=(address=(protocol=tcp)(host=anyhost)(port=1830))

If you do not want to use the default addresses, you must create a cman.ora file with the following information:

cman=(address=(protocol_address_information))
cman_admin=(address=(protocol_address_information))

A cman.ora file should exist in $ORACLE_HOME/network/admin on UNIX and ORACLE_HOME\network\admin on Windows NT that you can modify.

See Also: "Oracle Connection Manager Parameters (cman.ora)" for more information about the cman.ora file Appendix B for more information about protocol syntax needed for address information

Note: Net8 Assistant does not support configuration of the cman.ora file, so changes must be made manually.

Task 2: Configure Clients

Client support is accomplished by creating two addresses, the first for the Oracle Connection Manager and the second for the listener. Configuration varies according to naming method, as described in the following table:

Naming Method	Procedure
Local Naming and Directory Naming	An address list must be created, where the first address must be for the Oracle Connection Manager, and the second address must be for the listener. In order to have the client connect to the Oracle Connection Manager first and have the Oracle Connection Manager then connect to the listener, the SOURCE_ROUTE parameter must be set. See Also: "Configuring Clients for Oracle Connection Manager" to configure the Oracle Connection Manager and listener addresses
Oracle Names	Oracle Names servers are automatically updated with the listener and Oracle Connection Manager addresses. In order for a client using an Oracle Names server to send requests to Oracle Connection Manager, the USE_CMAN=TRUE parameter must be set in the sqlnet.ora file on clients and machines where each Oracle Names server resides. To set this parameter, follow the procedure in "Routing Connection Requests".

Example 8-2 depicts a client using SPX to connect to an Oracle Connection Manager, and Oracle Connection Manager using TCP/IP to connect to a database server.

Example 8-2 CMAN Parameter Configured to Use Multi-Protocol Support

cman=
   (description=
      (source_route=yes) 
      (address=
            (protocol=spx) 
            (service=cman))
      (address=
            (protocol=tcp) 
            (host=sales-pc) 
            (port=1521))
      (connect_data=
            (service_name=sales.com)))

tnsnames.ora File Element	Description
source_route=yes	Creates a source route of addresses through an Oracle Connection Manager to the destination database.
(address= (protocol=spx) (service=cman))	This first address is from a client using SPX to the Oracle Connection Manager. From here, the Oracle Connection Manager connects to the database service using TCP/IP through the listener.

Enabling Net8 Access Control

Oracle Connection Manager also includes a feature which you can use to control client access to designated servers in a TCP/IP environment. By specifying certain filtering rules, you may allow or restrict specific clients access to a server.

Use of this feature depends on whether you want to use connection concentration and multi-protocol support features with or without filtering.

This feature requires the release 8.1 Oracle Connection Manager if there are release 8.1 services in the network.

To configure Net8 access control, perform these tasks:

Task 1: Configure Oracle Connection Manager

Task 2: Configure Clients

Task 1: Configure Oracle Connection Manager

To configure the Oracle Connection Manager:

1. Manually create a cman.ora file, if one does not already exist. Net8 Assistant does not support configuration of this file.

   A cman.ora file should exist in $ORACLE_HOME/network/admin on UNIX and ORACLE_HOME\network\admin on Windows NT that you can edit.

   See Also: "Oracle Connection Manager Parameters (cman.ora)" for more information about the cman.ora file Appendix B for more information about protocol syntax needed for address information

2. If you do not want to use the default listening port of 1630 for client connections, add the following:

   cman=(address=(protocol=tcp)(host=anyhost)(port=port))
   
   

3. If you do not want to use the default listening port of 1830 for administration commands, add the following:

   cman=(address=(protocol=tcp)(host=anyhost)(port=port))
   
   

4. Add the CMAN_RULES parameter with the following parameters:

   cman_rules=
    (rule_list=
      (rule=
        (src=shost) 
        (dst=dhost) 
        (srv=service) 
        (act=accept | reject)))
   

   Parameter	Description
   SRC	Source host name or IP address (client)
   DST	Destination host name or IP address (server)
   SRV	Service name of the release 8.1 database (obtained from the SERVICE_NAME parameter in the initialization parameter file) or SID value of the pre-release 8.1 database (obtained from the ORACLE_SID environment variable or registry value)
   ACT	Accept or reject the incoming requests based on the above three parameters.

   Multiple RULEs can be defined within the RULE_LIST. The action (ACT) in the first matched RULE is applied to the request. If the CMAN_RULES are not defined, then all connections are permitted.

   The following example shows restriction to service sales.us.acme.com for a client machine of client1-pc, and access to service db1 for client 144.25.23.45.

   cman_rules=
    (rule_list=
       (rule=(src=client1-pc)(dst=sales-pc)(srv=sales.us.acme.com)(act=reject)) 
       (rule=(src=144.25.23.45)(dst=144.25.187.200)(srv=db1)(act=accept)))
   

Task 2: Configure Clients

Client support is accomplished by creating two addresses, the first for the Oracle Connection Manager and the second for the listener. Configuration varies according to naming method, as described in the following table:

Naming Method	Procedure
Local Naming and Directory Naming	An address list must be created, where the first address must be for the Oracle Connection Manager, and the second address must be for the listener. In order to have the client connect to the Oracle Connection Manager first and have the Oracle Connection Manager then connect to the listener, the SOURCE_ROUTE parameter must be set. See Also: "Configuring Clients for Oracle Connection Manager" to configure the Oracle Connection Manager and listener addresses
Oracle Names	Oracle Names servers are automatically updated with the listener and Oracle Connection Manager addresses. In order for a client using an Oracle Names server to send requests to Oracle Connection Manager, the USE_CMAN=TRUE parameter must be set in the sqlnet.ora file on clients and machines where each Oracle Names server resides. To set this parameter, follow the procedure in "Routing Connection Requests".

Configuring Clients for Oracle Connection Manager

Note: If more than one Oracle Connection Manager is used in the connection path, you cannot use Oracle Names to connect clients through it.

Configuring the client involves routing client connection requests that you want concentrated to the database server through an Oracle Connection Manager. This is achieved by setting the Oracle Connection Manager and listener protocol addresses in a tnsnames.ora file, directory or an Oracle Names server. Take note of the following:

• If using Oracle Names servers, the Oracle Connection Manager automatically updates the addresses in the Oracle Names servers, inserting the address for the Oracle Connection Manager into the existing addresses. In order for Oracle Names servers to send requests to Oracle Connection Manager, USE_CMAN=TRUE must be set in the sqlnet.ora file on machines where each Oracle Names server resides. To set this parameter, follow the procedure in "Routing Connection Requests".

• If using a tnsnames.ora file or a directory, the protocol addresses and the SOURCE_ROUTE parameter must be set. To configure the local or directory naming methods for Oracle Connection Manager, perform these tasks:

  Task 1: Configure an Oracle Connection Manager Address

  Task 2: Configure the Listener Address

Task 1: Configure an Oracle Connection Manager Address

To configure an Oracle Connection Manager address:

1. Start Net8 Assistant:
   • On UNIX, run netasst from $ORACLE_HOME/bin.

   • On Windows NT, choose Start > Programs > Oracle - HOME_NAME > Network Administration > Net8 Assistant.

2. In the navigator pane, expand Directory or Local. Then select Service Naming.

3. Click "+" from the toolbar, or select Create from the Edit menu.

   The Net Service Name Wizard starts.

4. Enter any name in the Net Service Name field, then click Next:

   
   

5. Select the protocol the Oracle Connection Manager is configured to listen on, then click Next. By default this protocol is TCP/IP.

   
   

6. Enter network protocol information for the Oracle Connection Manager, then click Next. If you are using TCP/IP, the default port is 1630.

   
   

   See Also: Appendix B for protocol parameter settings

7. Select a release, enter a destination service, then click Next:

   
   

   If the destination service is Oracle release 8.1, click (Oracle8i), and enter a service name in the Service Name field. If destination service is Oracle release 8.0 or version 7 database, click (Oracle8 or Previous), and enter an Oracle System Identifier (SID) in the Database SID field.

   See Also: "Understanding Connect Descriptors" for further information about setting the service name string

8. Click Next.

   Note: Do not click Test, as a connection cannot be tested at this point.

9. Click Finish to save your configuration and dismiss Net Service Name Wizard.

   The new net service name and the Oracle Connection Manager address is added to the Service Naming folder.

Task 2: Configure the Listener Address

After the Oracle Connection Manager address is specified, create an address for the listener, so that the Oracle Connection Manager can connect to the server.

To configure the listener address:

1. Click the net service name you created in "Task 1: Configure an Oracle Connection Manager Address".

   Notice the Oracle Connection Manager address is displayed in the Address 1 tab:

   
   
2. Click "+".

   A new address tab displays.

3. Select the protocol, then enter protocol information for the listener. If you are using TCP/IP, the default port number is 1521:

   
   

   See Also: Appendix B for protocol parameter settings

4. In the Address Configuration box, click Advanced.

   The Address List Options dialog box appears:

   
   
5. Select "Use each address in order until destination reached", then click OK.

   This option sets SOURCE_ROUTE=ON. It tells the client to connect to the first address, the Oracle Connection Manager, and from the first address to the second address, the listener.

   Note: There is not an option that supports client load balancing and connect-time failover options with Oracle Connection Manager's source routing feature within the same address list. When SOURCE_ROUTE is set, the first address is for the client connection to an Oracle Connection Manager and the second address is for the Oracle Connection Manager connection to a listener. Client load balancing and connect-time failover are disabled when SOURCE_ROUTE is set. It is possible to manually configure client load balancing and connect-time failover with source routing for multiple address lists. See "Examples".

6. In the right pane, click Apply.

Configuring Connections to Non-Oracle Database Services

The following sections describes how to configure connections to non-Oracle database services:

• Configuring Net8 for External Procedures

• Configuring Net8 for Oracle Heterogeneous Services

• Configuring Net8 for an Oracle Rdb Database

Configuring Net8 for External Procedures

External procedures are functions or procedures written in a third-generation language (3GL) that can be called from PL/SQL code.

The listener can be configured to listen for external procedure calls. When a PL/SQL or SQL application calls an external procedure, the listener launches a network session-specific process called extproc. Through the listener service, PL/SQL passes the following information to extproc:

• Shared library name

• External procedure name

• Parameters (if necessary)

extproc then loads the shared library and invokes the external procedure.

By default, Net8 Configuration Assistant configures connections to external procedure during server installation. For environments where the connection information do not exist, edit the listener.ora file and tnsnames.ora files, located in $ORACLE_HOME/network/admin on UNIX and ORACLE_HOME\network\admin on Windows platforms, as follows:

1. Configure either a TCP/IP or IPC listening address in the listener.ora file. The following procedures describes creating an IPC address:
   1. Start Net8 Assistant:

      -On UNIX, run netasst from $ORACLE_HOME/bin.

      -On Windows NT, choose Start > Programs > Oracle - HOME_NAME > Network Administration > Net8 Assistant.

   2. In the navigator pane, expand Local > Listeners.

   3. Select a listener.

   4. From the list in the right pane, select Listening Locations.

   5. Click Add Address. A new address tab appears.

      
      

   6. Select IPC from the Protocol list, and enter a value for the KEY. Oracle Corporation recommends a KEY value of extproc.

      Note: If your machine has more than one Oracle home or more than one listener, each listener must specify a unique KEY. Oracle Corporation recommends using extproc1 for the first listener, extproc2 for the second listener, and so on.

      See Also: "Configuring Listener Protocol Addresses" for more information about configuring listener protocol addresses

2. Add service information about extproc in the listener.ora file, including the following parameters:

   listener.ora Parameter	Net8 Assistant Field	Description
   SID_NAME	SID	Specifies the Oracle System Identifier (SID) for the non-Oracle database
   ORACLE_HOME	Oracle Home Directory	Specifies the Oracle home location of the extproc program
   PROGRAM	Program Name	Specifies the name of the extproc executable

   To configure the SID_NAME, ORACLE_HOME, and PROGRAM parameters:

   1. From the list in the right pane, select Other Services.

   2. Click Add Service. A new Service tab appears:

      
      

   3. Enter extproc in the Program Name field, a SID, such as plsextproc, in the SID field, and the Oracle home where the extproc executable resides in the Oracle Home field,

   4. Choose File > Save Network Configuration.

      The listener.ora file updates with external procedures, as shown in the following:

      listener=
        (address=
           (protocol=ipc)
           (key=extproc))
      sid_list_listener
        (sid_list=
          (sid_desc=                 
           (sid_name=plsextproc)
           (oracle_home=/u1/app/oracle/8.1.6)
           (program=extproc))) 
      
      

3. Create a net service name in the server's tnsnames.ora file that matches the information configured in the listener.ora file.

4. Based on the listener.ora file shown in Step 2, the tnsnames.ora file should be configured with the following entry:

   extproc_connection_data=            
    (description=                     
      (address=(protocol=ipc)(key=extproc))                      
      (connect_data=
       (sid=plsextproc))) 
   

   See Also: "Configuring the Local Naming Method" for more information about creating a net service name

Configuring Net8 for Oracle Heterogeneous Services

Heterogeneous Services are an integrated component within the Oracle server, and provides the generic technology for accessing non-Oracle systems from the Oracle server. Heterogeneous Services enable you to:

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

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

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

To initiate a connection to the non-Oracle system, the Oracle server starts an agent process through the listener on the gateway. For the Oracle server to be able to connect to the agent, perform the following steps:

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

   listener.ora Parameter	Net8 Assistant Field	Description
   SID_NAME	SID	Specifies the Oracle System Identifier (SID)
   ORACLE_HOME	Oracle Home	Specifies the Oracle home location of the agent executable
   PROGRAM	Program Name	Specifies the name the agent executable

   To configure the SID, ORACLE_HOME, and PROGRAM parameters:

   1. Start Net8 Assistant:

      -On UNIX, run netasst from $ORACLE_HOME/bin.

      -On Windows NT, choose Start > Programs > Oracle - HOME_NAME > Network Administration > Net8 Assistant.

   2. In the navigator pane, expand Local > Listeners.

   3. Select a listener.

   4. From the list in the right-pane, select Other Services.

   5. Click Add Service. A new service tab appears:

      
      

   6. Enter the program name in the Program Names field that gets executed to create a gateway, the Oracle home where the agent executable resides in the Oracle Home field, and the SID or service name of the non-Oracle system in the SID field.

   7. Choose File > Save Network Configuration.

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

      sid_list_listener=
       (sid_list=
        (sid_desc=
         (sid_name=salesdb)
         (oracle_home=/home/oracle/megabase/8.1.6)
         (program=tg4mb80)))
      

      See Also: Oracle8i Distributed Database Systems

2. On the machine where the Oracle database resides, set up a net service name to connect to the listener on the gateway. The connect descriptor must also include the HS=OK clause to make sure the connection uses Heterogeneous Services:
   1. Start Net8 Assistant:

      -On UNIX, run netasst from $ORACLE_HOME/bin.

      -On Windows NT, choose Start > Programs > Oracle - HOME_NAME > Network Administration > Net8 Assistant.

   2. Create a net service name that can be used for connections from the Oracle server to a non-Oracle system.

      See Also: "Task 1: Configure Net Service Names" for net service name creation for local naming

   3. In the navigator pane, expand Local > Service Naming.

   4. Select the net service name.

   5. Click Advanced in the Service Identification group box.

      The Advanced Service Options dialog box appears:

      
      
   6. Click Use for Heterogeneous Service, then click OK.

   7. Choose File > Save Network Configuration.

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

      megabase6_sales=
       (description=
        (address=(protocol=tcp)(host=dlsun206)(port=1521))
        (connect_data=
          (service_name=sales6)
          (hs=ok)))
      

Configuring Net8 for an Oracle Rdb Database

Oracle Rdb is a database for Digital's 64-bit platforms. With Net8, Oracle Rdb servers appears the same way to clients as Oracle8i databases. Because Oracle Rdb has its own listener, the client interacts with Rdb in the same manner as it does with Oracle7.

To initiate a connection to an Oracle Rdb, set up a net service name to connect to the Oracle Rdb database using the parameters described in the following table:

tnsnames.ora Parameter	Net8 Assistant Field	Description
RDB_DATABASE	RDB Database	Specifies the file name of an Oracle RDB database. Embed this parameter in the CONNECT_DATA section
TYPE_OF_SERVICE	Type of Service	Specifies the type of service to use for an Oracle RDB database. It is used by Rdb interface tools. This feature should only be used if the application supports both an Oracle Rdb and Oracle database, and you want the application to randomly choose (load balance). Embed this parameter in the DESCRIPTION.
GLOBAL_NAME	Global Database Name	An optional feature, it identifies the Oracle Rdb database. Embed this parameter in the CONNECT_DATA section.

To configure a client for an Oracle Rdb database, use Net8 Assistant:

1. Start Net8 Assistant:
   • On UNIX, run netasst from $ORACLE_HOME/bin.

   • On Windows NT, choose Start > Programs > Oracle - HOME_NAME > Network Administration > Net8 Assistant.

2. Create a net service name that can be used for connections from the Oracle8i server to a non-Oracle system.

   See Also: "Task 1: Configure Net Service Names" for net service name creation for local naming

3. In the navigator pane, expand Directory or Local > Service Naming.

4. Select the net service name.

5. Click Advanced in the Service Identification group box.

   The Advanced Service Options dialog box appears:

   
   
6. Enter the file name of an Oracle Rdb database in the Rdb Database field.

7. Optionally, enter the global database name in the Global Database Name field, and, if needed, specify the type of service in the Type of Service field, then click OK.

8. Choose File > Save Network Configuration.

   The tnsnames.ora file updates with the new net service name configured for the Oracle Rdb database, as shown in the following:

   alpha5=
     (description=
       (address=...)
       (connect_data=
         (service_name=generic)
         (rbd_database=[.mf]mf_personnel.rdb)
        (global_name=alpha5)))
   

   In the following example, TYPE_OF_SERVICE is used to load balance between an Oracle Rdb database service or Oracle database service:

   alpha5=
    (description_list=
     (description=
       (address=...)
       (connect_data=
        (service_name=generic)
        (rbd_database=[.mf]mf_personnel.rdb)
        (global_name=alpha5)))
    (description=
      (address=...)
       (connect_data=
        (service_name=sales.com))
       (type_of_service=oracle8_database))
   

   See Also: Oracle Rdb documentation