orbd(1)orbd(1)Nameorbd - The Object Request Broker Daemon
orbd is used to enable clients to transparently locate and invoke
persistent objects on servers in the CORBA environment.
See also: Naming Service @
http://java.sun.com/javase/6/docs/technotes/guides/idl/jidlNam‐
ing.html
SYNOPSISorbd <options>
DESCRIPTION
The Server Manager included with the orbd tool is used to enable
clients to transparently locate and invoke persistent objects on
servers in the CORBA environment. The persistent servers, while pub‐
lishing 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 an ORBD port number in the
object reference for persistent object references has the following
advantages:
o 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.
o The client needs to lookup the object reference in the Naming Ser‐
vice only once, and can keep re-using this reference independent
of the changes introduced due to server life cycle.
To access ORBD's Server Manager, the server must be started using
servertool(1), which is a command-line interface for application pro‐
grammers 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.
When orbd starts up, it also starts a naming service. For more informa‐
tion on the naming service, link to Naming Service @
http://java.sun.com/javase/6/docs/technotes/guides/idl/jidlNaming.html.
OPTIONS
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 rec‐
ommend that you use a port number greater than or equal to 1024.
(required)
OTHER OPTIONS
-port port
Specifies the activation port where ORBD should be started, and
where ORBD will be accepting requests for persistent objects. 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 ORBD checks for the health of persistent
servers registered via servertool. The default value is 1,000 ms.
The value specified for milliseconds must be a valid positive
integer. (optional)
-serverStartupDelay milliseconds
Specifies how long ORBD waits before sending a location forward
exception after a persistent server that is registered via
servertool is restarted. The default value is 1,000 ms. The value
specified for milliseconds must be a valid positive integer.
(optional)
-Joption
Pass option to the Java virtual machine, where option is one of
the options described on the reference page for 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 vir‐
tual machine.
Starting and Stopping the Naming Service
A Naming Service is a CORBA service that allows CORBA objects @
http://java.sun.com/javase/6/docs/technotes/guides/idl/jidlGlos‐
sary.html#CORBA%20object to be named by means of binding a name to an
object reference. The name binding @
http://java.sun.com/javase/6/docs/technotes/guides/idl/jidlGlos‐
sary.html#name%20binding 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 Persistent Naming Service will restore the nam‐
ing 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, enter:
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 applica‐
tions. 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 follow‐
ing code to your application:
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 specify the port number and/or machine name
when running the server or client application from the command 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 service may
disappear when the service is terminated if the naming service is tran‐
sient. The Java IDL naming service will run until it is explicitly
stopped.
For more information on the Naming Service included with ORBD, see Nam‐
ing Service @
http://java.sun.com/javase/6/docs/technotes/guides/idl/jidlNaming.html.
Server Manager
To access ORBD's Server Manager and run a persistent server, the server
must be started using servertool(1), which is a command-line interface
for application programmers to register, unregister, startup, and shut‐
down 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 @
http://java.sun.com/javase/6/docs/technotes/guides/idl/jidlExample.html
for our demonstration, you would run the idlj compiler and javac com‐
piler as shown in the tutorial. To run the Server Manager, follow these
steps for running the application:
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.
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, -ORBInitialPort 1050. The servertool must be started
on the same port as the name server.
The servertool command line interface appears.
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 "Hel‐
loServerApName", and displays its server id, along with a listing of
all registered servers.
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 nameserver‐
host 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.
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 continue 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
o Naming Service @
http://java.sun.com/javase/6/docs/technotes/guides/idl/jidlNam‐
ing.html
o servertool(1)
20 Mar 2008 orbd(1)
