orbd(1) orbd(1)
NAME
orbd - The Object Request Broker Daemon
orbd is used to enable clients to transparently locate and invoke persistent objects on servers in
the CORBA environment.
SYNOPSIS
orbd [ options ]
DESCRIPTION
The Server Manager included with the orbd tool is used to enable clients to transparently locate and
invoke persistent objects on server in the CORBA environment. The persistent servers, while publish-ing publishing
ing the persistent object references in the Naming Service, include the port number of the ORBD in
the object reference instead of the port number of the Server. The inclusion of ORBD port number in
the object reference for persistent object references has the following advantages:
The object reference in the Naming Service remains
independent of the server life cycle. For example, the object reference could be published by the
server in the Naming Service when it is first installed, and then independent of how many times the
server is started or shutdown, the ORBD will always return the correct object reference to the
invoking client.
The client needs to lookup the object reference in
the Naming Service only once, and can keep re-using this reference independent of the chanes intro-duced introduced
duced due to server life cycle.
To access ORBD's Server Manager, the server must be started using servertool, which is a command-line
interface for application programmers to register, unregister, startup, and shutdown a persistent
server. For more information on the Server Manager, see the section in this document titled Server
Manager.
REQUIRED OPTIONS
-ORBInitialPort nameserverport
Specifies the port on which the name server should be started. Once started, orbd will listen
for incoming requests on this port. Note that when using Solaris software, you must become
root to start a process on a port under 1024. For this reason, we recommend that you use a
port number greater than or equal to 1024. (required)
OTHER OPTIONS
-port port
Specifies the activation port where the ORBD should be started. The default value for this
port is 1049. This port number is added to the port field of the persistent Interoperable
Object References (IOR). (optional)
-defaultdb directory
Specifies the base where the ORBD persistent storage directory orb.db is created. If this
option is not specified, the default value is "./orb.db". (optional)
-serverPollingTime milliseconds
Specifies how often the daemon thread checks for the health of registered servers. ORBD polls
process health every milliseconds. The default value is 1,000 ms (or 1 second). The value
specified for milliseconds must be a valid integer.
-serverStartupDelay milliseconds
Specifies how long the ServerManager waits before sending a location forward exception after
the server is restarted. ORBD waits for milliseconds before raising a location forward excep-tion. exception.
tion. The default value is 1,000 ms (or 1 second). The value specified for milliseconds must
be a valid integer.
-Joption
Pass option to the Java virtual machine, where option is one of the options described on the
man page for the java application launcher, java(1). For example, -J-Xms48m sets the startup
memory to 48 megabytes. It is a common convention for -J to pass options to the underlying
virtual machine.
Starting and Stopping the Name Service
A Naming Service is a CORBA service that allows CORBA objects to be named by means of binding a name
to an object reference. The name binding may be stored in the naming service, and a client may supply
the name to obtain the desired object reference.
Prior to running a client or a server, you will start ORBD. ORBD includes a persistent Naming Service
and a transient Naming Service, both of which are an implementation of the COS Naming Service.
The Persistent Naming Service provides persistence
for naming contexts. This means that this information is persistent across service shutdowns and
startups, and is recoverable in the event of a service failure. If ORBD is restarted, the Persis-tent Persistent
tent Naming Service will restore the naming context graph, so that the binding of all clients' and
servers' names remains intact (persistent).
For backward compatibility, tnameserv, a
Transient Naming Service shipped with older versions of the JDK, is also included in this release
of J2SE. A transient naming service retains naming contexts as long as it is running. If there is a
service interruption, the naming context graph is lost.
The -ORBInitialPort argument is a required command-line argument for orbd, and is used to set the
port number on which the Naming Service will run. The following instructions assume you can use port
1050 for the Java IDL Object Request Broker Daemon. When using Solaris software, you must become root
to start a process on a port under 1024. For this reason, we recommend that you use a port number
greater than or equal to 1024. You can substitute a different port if necessary.
TO start orbd from a UNIX command shell, enterL
orbd -ORBInitialPort 1050&
From an MS-DOS system prompt (Windows), enter:
start orbd -ORBInitialPort 1050
Now that ORBD is running, you can run your server and client applications. When running the client
and server applications, they must be made aware of the port number (and machine name, if applicable)
where the Naming Service is running. One way to do this is to add the following code to your applica-tion: application:
tion:
Properties props = new Properties();
props.put("org.omg.CORBA.ORBInitialPort", "1050");
props.put("org.omg.CORBA.ORBInitialHost", "MyHost");
ORB orb = ORB.init(args, props);
In this example, the Naming Service is running on port 1050 on host "MyHost". Another way is to spec-ify specify
ify the port number and/or machine name when running the server or client application from the com-mand command
mand line. For example, you would start your "HelloApplication" with the following command line:
java HelloApplication -ORBInitialPort 1050 -ORBInitialHost MyHost
To stop the naming service, use the relevant operating system command, such as pkill orbd on Solaris,
or Ctrl+C in the DOS window in which orbd is running. Note that names registered with the naming ser-vice service
vice may disappear when the service is terminated if the naming service is transient. The Java IDL
naming service will run until it is explicitly stopped.
For more information on the Naming Service included with ORBD, see Naming Service.
Server Manager
To access ORBD's Server Manager and run a persistent server, the server must be started using server-tool, servertool,
tool, which is a command-line interface for application programmers to register, unregister, startup,
and shutdown a persistent server. When a server is started using servertool, it must be started on
the same host and port on which orbd is executing. If the server is run on a different port, the
information stored in the database for local contexts will be invalid and the service will not work
properly.
Server Manager: an Example
Using the sample tutorial for our demonstration, you would run the idlj compiler and javac compiler
as shown in the tutorial. To run the Server Manager, follow these steps for running the application:
1. Start orbd.
To start orbd from a UNIX command shell, enter:
orbd -ORBInitialPort 1050
From an MS-DOS system prompt (Windows), enter:
start orbd -ORBInitialPort 1050
Note that 1050 is the port on which you want the name server to run. -ORBInitialPort is a required
command-line argument. When using Solaris software, you must become root to start a process on a port
under 1024. For this reason, we recommend that you use a port number greater than or equal to 1024.
2. Start the servertool:
To start the Hello server, enter:
servertool -ORBInitialPort 1050
Make sure the name server (orbd) port is the same as in the previous step, for example, -ORBInitial-Port -ORBInitialPort
Port 1050. The servertool must be started on the same port as the name server.
3. Start the Hello server from the servertool prompt:
servertool > register -server HelloServer -classpath .
-applicationName HelloServerApName
The servertool registers the server, assigns it the name of "HelloServerApName", and displays its
server id.
4. Run the client application from another terminal window or prompt:
java HelloClient -ORBInitialPort 1050 -ORBInitialHost localhost
For this example, you can omit -ORBInitialHost localhost since the name server is running on the same
host as the Hello client. If the name server is running on a different host, use -ORBInitialHost
nameserverhost to specify the host on which the IDL name server is running.
Specify the name server (orbd) port as done in the previous step, for example, -ORBInitialPort 1050.
5. When you have finished experimenting with the Server Manager, be sure to shut down or kill the
name server (orbd) and servertool.
To shut down orbd from a DOS prompt, select the window that is running the server and enter Ctrl+C to
shut it down. To shut down orbdfrom a Unix shell, find the process, and kill it. The server will con-tinue continue
tinue to wait for invocations until it is explicitly stopped.
To shut down the servertool, type quit and press the Enter key on the keyboard.
SEE ALSO
Naming Service, servertool
10 March 2001 orbd(1)
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