orbd

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.

          See also: Naming Service

SYNOPSIS
       orbd 


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,  which is a command-line interface for application program‐
       mers 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.

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 the java applica‐
             tion  launcher. 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 Naming 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 bind‐
       ing  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.

Server Manager
       To access ORBD's Server Manager and run a persistent server, 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. 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  data‐
       base  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:

       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

          o servertool


                                  07 Aug 2006                          orbd(1)