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This chapter explains how to configure connections from remote BEA Tuxedo CORBA client applications to CORBA objects via the standard Internet Inter-ORB Protocol (IIOP). This chapter is specific to BEA Tuxedo CORBA servers.
| Note: | The BEA Tuxedo CORBA Java client and BEA Tuxedo CORBA Java client ORB were deprecated in Tuxedo 8.1 and are no longer supported in Tuxedo 9.x. All BEA Tuxedo CORBA Java client and BEA Tuxedo CORBA Java client ORB text references, associated code samples, etc. should only be used: |
| Note: | Technical support for third party CORBA Java ORBs should be provided by their respective vendors. BEA Tuxedo does not provide any technical support or documentation for third party CORBA Java ORBs. |
This topic includes the following sections:
buildobjserver command. CORBA Servers implement BEA Tuxedo functionality, such as security, transactions, and object state management. Servers can make invocations on any server, inside or outside a BEA Tuxedo domain.
tmadmin, FactoryFinder, and ISL/ISH. Native clients use the environmental objects to access CORBA objects. You build native C++ clients with the buildobjclient command or native Java clients using the tools provided by the third-party ORB.
tmadmin, FactoryFinder, and ISL/ISH; it does contain supporting software (the CORBA ORB) that allows remote clients to invoke objects. Remote clients use the environmental objects to access CORBA objects. You build remote C++ clients with the buildobjclient command or remote Java clients using the tools provided by the third-party ORB.
buildobjclient command. Java native joint client/servers are not supported.
| Note: | The server role of the native joint client/server is considerably less robust than that of a server. It has none of the BEA Tuxedo CORBA administrative and infrastructure components, such as tmadmin, FactoryFinder, and ISL/ISH (hence none of BEA Tuxedo's scalability and reliability attributes), it does not use the BEA Tuxedo TP Framework, and it requires more direct interaction between the client and the ORB. |
buildobjclient command or remote Java client/servers using the tools provided by the third-party ORB.
| Note: | A joint client/server is different from a server that acts as a client as part of its server role. Once the server completes processing of an invocation, it returns to dormancy. A joint client/server is always in the active mode, executing code not related to a server role; the server role temporarily interrupts the active client role, but the client role is always resumed. |
| Note: | The server role of the remote joint client/server is considerably less robust than that of a server. Neither the client nor the server has any of the BEA Tuxedo administrative and infrastructure components, such as tmadmin, FactoryFinder, and ISL/ISH (hence, none of BEA Tuxedo's scalability and reliability attributes). |
In this section, the term "remote client" represents a CORBA client application that is deployed on systems that do not have the full BEA Tuxedo CORBA server software installed. This means that no administration or application servers are running there and that no bulletin board is present. All communication between the client and the application takes place over the network.
A client process can run on UNIX or Microsoft Windows. The client has access to the CORBA ORB interface. The networking behind the calls is transparent to the user. The client process registers with the system and has the same status as a native client.
The client can do the following:
| Note: | A client process communicates with the native domain through the ISH. |
Figure 14-1 shows an example of an application with remote clients connected. Any request by a remote client to access the CORBA server application is sent over the network to the ISH. This process sends the request to the appropriate server and sends the reply back to the remote client.
The client connects to the ISL process in the IIOP Listener/Handler using a known network address. This is initiated when the client calls the Bootstrap object constructor. The ISL process uses a function that is specific to the operating system to pass the connection directly to the selected ISH process. To the client application, there is only one connection. The client application does not know, or need to know, that it is now connected to the ISH process.
For CORBA C++ clients, environment variables can be used to pass information to the system, as follows:
TUXDIR—the location of the BEA Tuxedo CORBA client software on this remote client. It must be set for the client to connect.TOBJADDR—the network address of the ISL that the client wants to contact. This must match the address of an ISL process as specified in the application configuration file.| Note: | The network address that is specified by programmers in the Bootstrap constructor or in TOBJADDR must exactly match the network address in the server application's UBBCONFIG file. The format of the address as well as the capitalization must match. If the addresses do not match, the call to the Bootstrap constructor will fail with a seemingly unrelated error message:ERROR: Unofficial connection from client at For example, if the network address is specified as //TRIXIE:3500 in the ISL command line option string (in the server application's UBBCONFIG file), specifying either //192.12.4.6:3500 or //trixie:3500 in the Bootstrap constructor or in TOBJADDR will cause the connection attempt to fail.On UNIX systems, use the uname -n command on the host system to determine the capitalization used. On Windows systems, see the host system's Network control panel to determine the capitalization used. Or use the environment variable COMPUTERNAME. For example:echo %COMPUTERNAME% |
To join remote clients to an application, you must specify the MAXWSCLIENTS parameter in the MACHINES section of the UBBCONFIG file.
MAXWSCLIENTS tells the BEA Tuxedo system at boot time how many accesser slots to reserve exclusively for remote clients. For native clients, each accesser slot requires one semaphore. However, the ISH process (executing on the native platform on behalf of remote clients) multiplexes remote client accessers through a single accesser slot and, therefore, requires only one semaphore. This points out an additional benefit of the remote extension. By putting more clients out on remote systems and taking them off the native platform, an application reduces its IPC resource requirements.
MAXWSCLIENTS takes its specified number of accesser slots from the total set in MAXACCESSERS. This is important to remember when specifying MAXWSCLIENTS; enough slots must remain to accommodate native clients as well as servers. Do not specify a value for MAXWSCLIENTS greater than MAXACCESSERS. The following table describes the MAXWSCLIENTS parameter.
Remote clients access your application through the services of an ISL process and one or more ISH processes. The ISL is specified in one entry as a server supplied by the BEA Tuxedo system. The ISL can support multiple remote clients and acts as the single point of contact for all the remote clients connected to your application at the network address specified on the ISL command line. The listener schedules work for one or more remote handler processes. An ISH process acts as a surrogate within the administrative domain of your application for remote clients on remote systems. The ISH uses a multiplexing scheme to support multiple remote clients concurrently.
To join remote clients to an application, you must list the ISL processes in the SERVERS section of the UBBCONFIG file. The processes follow the same syntax for listing any server.
You use the following ISL command-line options (CLOPT) to pass information to the ISL process for remote clients. The format of the CLOPT parameter is as follows:
ISL SRVGRP="identifier"
SRVID="number"
CLOPT="[ -A ] [ servopts options ] -- -n netaddr
[ -C {detect|warn|none} ]
[ -d device ]
[ -K {client|handler|both|none} ]
[ -m minh ]
[ -M maxh ]
[ -T client-timeout]
[ -x mpx-factor ]
[ -H external-netaddr"
For a detailed description of the CLOPT command line options, see the ISL command in the BEA Tuxedo Command Reference.
Listing 14-1 shows a sample UBBCONFIG file to support remote clients, as follows:
MACHINES section shows the default MAXWSCLIENTS as being overridden for two sites. For SITE1, the default is raised to 150, while it is lowered to 0 for SITE2, which does not have remote clients connected to it.SERVERS section shows an ISL process listed for group BANKB1. Its server ID is 500 and it is marked as restartable.-A).TRIXIE on port 2500.-d).-m).-M).-x).*MACHINES
SITE1
...
MAXWSCLIENTS=150
...
SITE2
...
MAXWSCLIENTS=0
...
*SERVERS
...
ISL SRVGRP="BANKB1" SRVID=500 RESTART=Y
CLOPT="-A -- -n //TRIXIE:2500 -d /dev/tcp
-m 5 -M 30 -x 5"
..
Support for outbound IIOP provides native clients and servers acting as native clients the ability to invoke on a remote object reference outside of the BEA Tuxedo domain. This means that calls can be invoked on remote clients that have registered for callbacks, and objects in remote servers can be accessed.
Administrators are the only users who interact directly with the outbound IIOP support components. Administrators are responsible for booting the ISLs with the correct startup parameters to enable outbound IIOP to objects not located in a connected client. Administrators may need to adjust the number of ISLs they boot and the various startup parameters to obtain the best configuration for their installation's specific workload characteristics.
Administrators have the option of booting the ISLs with the default parameters. However, the default BEA Tuxedo ISL startup parameters do not enable use of outbound IIOP.
| Note: | Outbound IIOP is not supported for transactions or security. |
Outbound IIOP support is required to support client callbacks. In BEA WebLogic Enterprise versions 4.0 and 4.1, the ISL/ISH was an inbound half-gateway. Outbound IIOP support adds the outbound half-gateway to the ISL/ISH. (See Figure 14-2.)
There are three types of outbound IIOP connections available, depending on the version of GIOP supported by the native server and the remote joint client/server application:
| Note: | GIOP 1.2 is supported only by BEA WebLogic Enterprise release 4.2 (and later) and BEA Tuxedo release 8.0 (and later) C++ clients, servers, and joint client/servers. BEA WebLogic Enterprise releases 4.0 and 4.1 C++ clients and servers support GIOP versions 1.0 and 1.1, but not GIOP 1.2. Java clients, servers, and joint client/servers only support GIOP 1.0. |
Bi-directional and dual-paired connection outbound IIOP provides outbound IIOP to object references located in joint client/servers connected to an ISH. Asymmetric outbound IIOP provides outbound IIOP to object references not located in a joint client/server connected to an ISH, and also allows BEA Tuxedo CORBA clients to invoke on any object reference, not only object references located in clients currently connected to an ISH.
Each type of outbound IIOP is described in more detail in the following sections.
With bidirectional outbound IIOP, the following operations are executed (see Figure 14-3):
With asymmetric outbound IIOP, the following operations are executed (see Figure 14-4):
string_to_object, or it could be passed in through a client, but not located in that client. Since the object reference is not located in a client connected to an ISH, the outgoing call cannot be made using the bidirectional method. The BEA Tuxedo CORBA server invokes on the object reference. With dual-paired connection outbound IIOP, the following operations are executed (see Figure 14-5):
register_callback_port) and passes the object reference. register_callback_port call, the ISH creates a service context containing the host/port. The service context travels with the message to the BEA Tuxedo CORBA server. The steps to finding an ISL are as follows:
| Note: | Normal BEA Tuxedo routing is used to find an ISL. |
| Note: | Some invokes may be made to ISLs on nonlocal machines. |
Outbound IIOP support is used when a native C++ or Java client, or a server acting as a native client, invokes on an object reference that is a remote object reference. The routing code recognizes that the object reference is from a non-BEA Tuxedo CORBA ORB or from a remote BEA Tuxedo CORBA joint client/server.
There are two kinds of remote object references:
Both are detected by the routing code and sent to the outbound IIOP support for handling.
The user interface to outbound IIOP support is the commandline interface for booting the ISL process(es). New command-line options to configure the outbound IIOP processing were added to the ISL command in this release of the BEA Tuxedo software. These options enable support for asymmetric IIOP to object references not located in clients connected to an ISH.
The ISL command syntax listed below shows the new options for outbound IIOP support:
CLOPT="[ -A ] [ servopts options ] -- -n netaddr
[ -C {detect|warn|none} ]
[ -d device ]
[ -K {client|handler|both|none} ]
[ -m minh ]
[ -M maxh ]
[ -T Client-timeout]
[ -x mpx-factor ]
[-H external-netaddr]
#NEW options for outbound IIOP
[-O]
[-o outbound-max-connections]
[-s Server-timeout]
[-u out-mpx-users] "
For a detailed description of the CLOPT command-line options, see the ISL command in the BEA Tuxedo Command Reference.
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