path: root/lib/orber/doc/src/orber.xml

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<!DOCTYPE erlref SYSTEM "erlref.dtd">

<erlref>
  <header>
    <copyright>
      <year>1997</year><year>2016</year>
      <holder>Ericsson AB. All Rights Reserved.</holder>
    </copyright>
    <legalnotice>
      Licensed under the Apache License, Version 2.0 (the "License");
      you may not use this file except in compliance with the License.
      You may obtain a copy of the License at
 
          http://www.apache.org/licenses/LICENSE-2.0

      Unless required by applicable law or agreed to in writing, software
      distributed under the License is distributed on an "AS IS" BASIS,
      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
      See the License for the specific language governing permissions and
      limitations under the License.

    </legalnotice>

    <title>orber</title>
    <prepared></prepared>
    <responsible></responsible>
    <docno></docno>
    <approved></approved>
    <checked></checked>
    <date>1997-06-10</date>
    <rev>A</rev>
  </header>
  <module>orber</module>
  <modulesummary>The main module of the Orber application</modulesummary>
  <description>
    <p>This module contains the functions for starting and stopping the 
      application. It also has some utility functions to get some of 
      the configuration information from running application.</p>
  </description>
  <funcs>
    <func>
      <name>start() -> ok</name>
      <name>start(Type) -> ok</name>
      <fsummary>Start the Orber application</fsummary>
      <type>
        <v>Type = temporary | permanent</v>
      </type>
      <desc>
        <p>Starts the Orber application (it also starts mnesia if it is not running).
          Which <c>Type</c> parameter is supplied determines the behavior. If not
          supplied Orber is started as <c>temporary</c>. 
          See the Reference Manual <em>application(3)</em> for further information. </p>
      </desc>
    </func>
    <func>
      <name>jump_start(Attributes) -> ok | {'EXIT', Reason}</name>
      <fsummary>Start the Orber application during tests</fsummary>
      <type>
        <v>Attributes = Port | Options</v>
        <v>Port = integer()</v>
        <v>Options = [{Key, Value}]</v>
        <v>Key = any key listed in the configuration chapter</v>
        <v>Value = allowed value associated with the given key</v>
      </type>
      <desc>
        <p>Installs and starts the Orber and the Mnesia applications with the configuration
          parameters <c>domain</c> and <c>iiop_port</c> set to <c>"IP-number:Port"</c>
          and the supplied Port respectively. Theses settings are in most cases
          sufficient to ensure that no clash with any other Orber instance occur.
          If this operation fails, check if the listen port (iiop_port) is already
          in use. This function <em>MAY ONLY</em> be used during development and
          tests; how Orber is configured when using this operation may change 
          at any time without warning.</p>
      </desc>
    </func>
    <func>
      <name>stop() -> ok</name>
      <fsummary>Stop the Orber application</fsummary>
      <desc>
        <p>Stops the Orber application.</p>
      </desc>
    </func>
    <func>
      <name>info() -> ok</name>
      <name>info(IoType) -> ok | {'EXIT', Reason} | string()</name>
      <fsummary>Generate Info Report, which contain Orber's configuration  settings</fsummary>
      <type>
        <v>IoType = info_msg | string | io | {io, IoDevice}</v>
      </type>
      <desc>
        <p>Generates an Info Report, which contain Orber's configuration settings.
          If no <c>IoType</c> is supplied, <c>info_msg</c> is used (see the
          error_logger documentation). When the atom string is supplied this
          function will return a flat list. For <c>io</c> and <c>{io, IoDevice}</c>,
          <c>io:format/1</c> and <c>io:format/3</c> is used respectively.</p>
      </desc>
    </func>
    <func>
      <name>exception_info(Exception) -> {ok, string()} | {error, Reason}</name>
      <fsummary>Return a printable string, which describes the supplied  exception</fsummary>
      <desc>
        <p>Returns a printable string, which describes the supplied exception
          in greater detail. Note, this function is mainly intended for
          system exceptions.</p>
      </desc>
    </func>
    <func>
      <name>is_system_exception(Exception) -> true | false</name>
      <fsummary>Return true if the supplied exception is a system defined  exception otherwise false</fsummary>
      <desc>
        <p>Returns true if the supplied exception is a system defined 
          exception, otherwise false.</p>
      </desc>
    </func>
    <func>
      <name>get_tables() -> [Tables]</name>
      <fsummary>Get the Mnesia tables Orber uses.</fsummary>
      <desc>
        <p>Returns a list of the Orber specific Mnesia tables. This list is
          required to restore Mnesia if it has been partitioned.</p>
      </desc>
    </func>
    <func>
      <name>get_ORBInitRef() -> string() | undefined</name>
      <fsummary>Get the initial reference address.</fsummary>
      <desc>
        <p>This function returns undefined if we will resolve references locally,
          otherwise a string describing which host we will contact if the Key given
          to <c>corba:resolve_initial_references/1</c> matches the Key set
          in this configuration variable. For more information
          see the user's guide.</p>
      </desc>
    </func>
    <func>
      <name>get_ORBDefaultInitRef() -> string() | undefined</name>
      <fsummary>Get the initial reference address.</fsummary>
      <desc>
        <p>This function returns undefined if we will resolve references locally,
          otherwise a string describing which host, or hosts, from which we
          will try to resolve the Key given to 
          <c>corba:resolve_initial_references/1</c>. For more information
          see the user's guide.</p>
      </desc>
    </func>
    <func>
      <name>domain() -> string()</name>
      <fsummary>Display the Orber domain name</fsummary>
      <desc>
        <p>This function returns the domain name of the current Orber domain
          as a string.</p>
      </desc>
    </func>
    <func>
      <name>iiop_port() -> int()</name>
      <fsummary>Display the IIOP port number</fsummary>
      <desc>
        <p>This function returns the port-number, which is used by the IIOP
          protocol. It can be configured by setting the application variable 
          <em>iiop_port</em>, if it is not set it will have the default number
          4001.</p>
      </desc>
    </func>
    <func>
      <name>iiop_out_ports() -> 0 | {Min, Max}</name>
      <fsummary>Display the ports Orber may use when connecting to another ORB</fsummary>
      <desc>
        <p>The return value of this operation is what the configuration
          parameter <seealso marker="ch_install#config">iiop_out_ports</seealso>
          has been set to.</p>
      </desc>
    </func>

    <func>
      <name>iiop_out_ports_random() -> true | false</name>
      <fsummary>Determine if Orber should select local ports randomly</fsummary>
      <desc>
        <p>Return the value of the configuration parameter
           <seealso marker="ch_install#config">iiop_out_ports_random</seealso>.</p>
      </desc>
    </func>

    <func>
      <name>iiop_out_ports_attempts() -> int()</name>
      <fsummary>Display if Orber should accept more than one timeout connecting to another ORB</fsummary>
      <desc>
        <p>Return the value of the configuration parameter
           <seealso marker="ch_install#config">iiop_out_ports_attempts</seealso>.</p>
      </desc>
    </func>


    <func>
      <name>iiop_ssl_port() -> int()</name>
      <fsummary>Display the IIOP port number used for secure connections</fsummary>
      <desc>
        <p>This function returns the port-number, which is used by the secure IIOP
          protocol. It can be configured by setting the application variable 
          <em>iiop_ssl_port</em>, if it is not set it will have the default number
          4002 if Orber is to configured to run in secure mode. Otherwise it returns -1.</p>
      </desc>
    </func>
    <func>
      <name>iiop_timeout() -> int() (milliseconds)</name>
      <fsummary>Display the IIOP timeout value</fsummary>
      <desc>
        <p>This function returns the timeout value after which outgoing IIOP requests terminate.
          It can be configured by setting the application variable 
          <em>iiop_timeout TimeVal (seconds)</em>, if it is not set it will have the default value
          <em>infinity</em>. If a request times out a system exception, e.g.
          <em>TIMEOUT</em>, is raised.</p>
        <p>Note: the iiop_timeout configuration parameter (TimeVal) may only range between 0 and 1000000 seconds. 
          Otherwise, the default value is used.</p>
        <p>Note: Earlier IC versions required that the compile option <c>{timeout,"module::interface"}</c>,
          was used, which allow the user to add an extra timeout parameter, e.g., 
          <c>module_interface:function(ObjRef, Timeout, ... Arguments ...)</c> or
          <c>module_interface:function(ObjRef, [{timeout, Timeout}], ... Arguments ...)</c>, 
          instead of <c>module_interface:function(ObjRef, ... Arguments ...)</c>. 
          This is no longer the case and if the extra Timeout is used,
          argument will override the configuration parameter <c>iiop_timeout</c>.
          It is, however, not possible
          to use <c>infinity</c> to override the Timeout parameter. The Timeout
          option is also valid for objects which resides within the same Orber domain.</p>
      </desc>
    </func>
    <func>
      <name>iiop_connection_timeout() -> int() (milliseconds)</name>
      <fsummary>Display the IIOP connection timeout value</fsummary>
      <desc>
        <p>This function returns the timeout value after which outgoing IIOP connections terminate.
          It can be configured by setting the application variable 
          <em>iiop_connection_timeout TimeVal (seconds)</em>, if it is not set it will have the default value
          <em>infinity</em>. The connection will not be terminated if there are 
          pending requests.</p>
        <p>Note: the iiop_connection_timeout configuration parameter (TimeVal) may only range between 0 and 1000000 seconds. 
          Otherwise, the default value is used.</p>
      </desc>
    </func>
    <func>
      <name>iiop_connections() -> Result</name>
      <name>iiop_connections(Direction) -> Result</name>
      <fsummary>List all existing connections to/from other ORB's</fsummary>
      <type>
        <v>Direction = in | out | inout</v>
        <v>Result = [{Host, Port}] | [{Host, Port, Interface}] | {'EXIT',Reason}</v>
        <v>Host = string()</v>
        <v>Port = integer()</v>
        <v>Interface = string()</v>
        <v>Reason = term()</v>
      </type>
      <desc>
        <p>The list returned by this operation contain tuples of remote hosts/ports
          Orber is currently connected to. If no Direction is not supplied, both
          incoming and outgoing connections are included.</p>
        <p>If a specific local interface has been defined for the connection,
          this will be added to the returned tuple.</p>
      </desc>
    </func>
    <func>
      <name>iiop_connections_pending() -> Result</name>
      <fsummary>List all connections to another ORB currently being set up</fsummary>
      <type>
        <v>Result = [{Host, Port}] | [{Host, Port, Interface}] | {'EXIT',Reason}</v>
        <v>Host = string()</v>
        <v>Port = integer()</v>
        <v>Interface = string()</v>
        <v>Reason = term()</v>
      </type>
      <desc>
        <p>In some cases a connection attempt (i.e. trying to communicate with
          another ORB) may block due to a number of reasons. This operation
          allows the user to check if this is the case. The returned list
          contain tuples of remote hosts/ports. Normally, the list is empty.</p>
        <p>If a specific local interface has been defined for the connection,
          this will be added to the returned tuple.</p>
      </desc>
    </func>
    <func>
      <name>iiop_in_connection_timeout() -> int() (milliseconds)</name>
      <fsummary>Display the IIOP connection timeout value for incoming connections</fsummary>
      <desc>
        <p>This function returns the timeout value after which incoming IIOP 
          connections terminate. It can be configured by setting the application 
          variable <em>iiop_in_connection_timeout TimeVal (seconds)</em>, if it is
          not set it will have the default value <em>infinity</em>. The connection
          will not be terminated if there are pending requests.</p>
        <p>Note: the iiop_in_connection_timeout configuration parameter (TimeVal) may 
          only range between 0 and 1000000 seconds. Otherwise, the default value is
          used.</p>
      </desc>
    </func>
    <func>
      <name>iiop_acl() -> Result</name>
      <fsummary>Return the ACL configuration</fsummary>
      <type>
        <v>Result = [{Direction, Filter}] | [{Direction, Filter, [Interface]}]</v>
        <v>Direction = tcp_in | ssl_in | tcp_out | ssl_out</v>
        <v>Filter = string()</v>
        <v>Interface = string()</v>
      </type>
      <desc>
        <p>Returns the ACL configuration. The <c>Filter</c> uses a extended format of 
          Classless Inter Domain Routing (CIDR). For example, <c>"123.123.123.10"</c> limits
          the connection to that particular host, while <c>"123.123.123.10/17"</c> allows
          connections to or from any host equal to the 17 most significant bits. Orber
          also allow the user to specify a certain port or port range, for example,
          <c>"123.123.123.10/17#4001"</c> and <c>"123.123.123.10/17#4001/5001"</c>
          respectively. IPv4 or none compressed IPv6 strings are accepted.          <br></br>

          The list of <c>Interfaces</c>, IPv4 or IPv6 strings, are currently only used
          for outgoing connections and may only contain <em>one</em> address. If set and
          access is granted, Orber will use that local interface when connecting to the
          other ORB. The module <seealso marker="orber_acl">orber_acl</seealso>
          provides operations for evaluating the access control for filters and addresses.</p>
      </desc>
    </func>
    <func>
      <name>activate_audit_trail() -> Result</name>
      <name>activate_audit_trail(Verbosity) -> Result</name>
      <fsummary>Activate IIOP audit/trail</fsummary>
      <type>
        <v>Verbosity = stealth | normal | verbose</v>
        <v>Result = ok | {error, Reason}</v>
        <v>Reason = string()</v>
      </type>
      <desc>
        <p>Activates audit/trail for all existing incoming and outgoing IIOP
          connections. The <c>Verbosity</c> parameter, <c>stealth</c>, 
          <c>normal</c> or <c>verbose</c>, determines which of the built in
          interceptors is used (<c>orber_iiop_tracer_stealth</c>, 
          <c>orber_iiop_tracer_silent</c> or <c>orber_iiop_tracer</c> respectively).
          If no verbosity level is supplied, then the <c>normal</c> will be used.</p>
        <p>In case Orber is configured to use other interceptors, the audit/trail
          interceptors will simply be added to that list.</p>
      </desc>
    </func>
    <func>
      <name>deactivate_audit_trail() -> Result</name>
      <fsummary>Deactivate IIOP audit/trail</fsummary>
      <type>
        <v>Result = ok | {error, Reason}</v>
        <v>Reason = string()</v>
      </type>
      <desc>
        <p>Deactivates audit/trail for all existing incoming and outgoing IIOP
          connections. In case Orber is configured to use other interceptors, 
          those will still be used.</p>
      </desc>
    </func>
    <func>
      <name>add_listen_interface(IP, Type) -> Result</name>
      <name>add_listen_interface(IP, Type, Port) -> Result</name>
      <name>add_listen_interface(IP, Type, ConfigurationParameters) -> Result</name>
      <fsummary>Add a new listen process for incoming connection</fsummary>
      <type>
        <v>IP = string</v>
        <v>Type = normal | ssl</v>
        <v>Port = integer() > 0</v>
        <v>ConfigurationParameters = [{Key, Value}]</v>
        <v>Key = flags | ip_family | iiop_in_connection_timeout | iiop_max_fragments | iiop_max_in_requests | interceptors | iiop_port | iiop_ssl_port | ssl_server_options</v>
        <v>Value = as described in the User's Guide or below</v>
        <v>Result = {ok, Ref} | {error, Reason} | {'EXCEPTION', #'BAD_PARAM'{}}</v>
        <v>Ref = #Ref</v>
        <v>Reason = string()</v>
      </type>
      <desc>
        <p>Create a new process that handle requests for creating a new incoming
          IIOP connection via the given interface and port. If the latter is 
          excluded, Orber will use the value of the <c>iiop_port</c> or 
          <c>iiop_ssl_port</c> configuration parameters.
          The <c>Type</c> parameter determines if it is
          supposed to be IIOP or IIOP via SSL. If successful, the returned
          <c>#Ref</c> shall be passed to <c>orber:remove_listen_interface/1</c>
          when the connection shall be terminated.</p>
        <p>It is also possible to supply configuration parameters that override
          the global configuration. The <em>iiop_in_connection_timeout</em>,
          <em>iiop_max_fragments</em>, <em>iiop_max_in_requests</em> and
          <em>interceptors</em> parameters simply overrides the global
          counterparts (See the
          <seealso marker="ch_install#config">Configuration</seealso> chapter
          in the User's Guide). 
          But for the following parameters there are a few restrictions:</p>
        <list type="bulleted">
          <item><em>flags</em> - currently it is only possible to override the global
           setting for the <c>Use Current Interface in IOR</c> and 
          <c>Exclude CodeSet Component</c> flags.</item>
	  <item><em>ip_family</em> - can be set to <c>inet</c> or <c>inet6</c> and is 
	  used to get a listen interface that uses another IP version than the default
	  set with flags at startup.</item>
          <item><em>iiop_port</em> - requires that <c>Use Current Interface in IOR</c>
           is activated and the supplied <c>Type</c> is <c>normal</c>. If so,
           exported IOR:s will contain the IIOP port defined by this configuration
           parameter. Otherwise, the global setting will be used.</item>
          <item><em>iiop_ssl_port</em> - almost equivalent to <c>iiop_port</c>.
           The difference is that <c>Type</c> shall be <c>ssl</c> and that
           exported IOR:s will contain the IIOP via SSL port defined by this configuration
           parameter.</item>	
        </list>
        <p>If it is not possible to add a listener based on the supplied interface
          and port, the error message is one of the ones described in <c>inet</c>
          and/or <c>ssl</c> documentation.</p>
      </desc>
    </func>
    <func>
      <name>remove_listen_interface(Ref) -> ok</name>
      <fsummary>Terminate listen process for incoming connection</fsummary>
      <type>
        <v>Ref = #Ref</v>
      </type>
      <desc>
        <p>Terminates the listen process, associated with the supplied <c>#Ref</c>,
          for incoming a connection. The Ref parameter is the return value from
          the <c>orber:add_listen_interface/2/3</c> operation. When terminating
          the connection, all associated requests will not deliver a reply to
          the clients.</p>
      </desc>
    </func>
    <func>
      <name>close_connection(Connection) -> Result</name>
      <name>close_connection(Connection, Interface) -> Result</name>
      <fsummary>Terminate outgoing connection(s)</fsummary>
      <type>
        <v>Connection = Object | [{Host, Port}]</v>
        <v>Object = #objref (external)</v>
        <v>Host = string()</v>
        <v>Port = string()</v>
        <v>Interface = string()</v>
        <v>Result = ok | {'EXCEPTION', #'BAD_PARAM'{}}</v>
      </type>
      <desc>
        <p>Will try to close all outgoing connections to the host/port combinations
          found in the supplied object reference or the given list of hosts/ports.
          If a <c>#'IOP_ServiceContext'{}</c> containing a local interface has been
          used when communicating with the remote object
          (see also <seealso marker="Module_Interface">Module_Interface</seealso>), 
          that interface shall be passed as the second argument. Otherwise, connections
          via the default local interface, will be terminated.</p>
        <p></p>
        <note>
          <p>Since several clients maybe communicates via the same connection,
            they will be affected when invoking this operation. Other clients may
            re-create the connection by invoking an operation on the target object.</p>
        </note>
      </desc>
    </func>
    <func>
      <name>secure() -> no | ssl</name>
      <fsummary>Display the security mode Orber is running in</fsummary>
      <desc>
        <p>This function returns the security mode Orber is running in, which is either no if it is an 
          insecure domain or the type of security mechanism used. For the moment the only security 
          mechanism is ssl. This is configured by setting the application variable 
          <em>secure</em>.</p>
      </desc>
    </func>
    <func>
      <name>ssl_server_options() -> list()</name>
      <fsummary>Display the SSL server options</fsummary>
      <desc>
        <p>This function returns the list of SSL options set for the Orber domain as server. 
          This is configured by setting the application variable 
          <em>ssl_server_options</em>.</p>
      </desc>
    </func>
    <func>
      <name>ssl_client_options() -> list()</name>
      <fsummary>Display the SSL client options</fsummary>
      <desc>
        <p>This function returns the list of SSL options used in outgoing calls in the current process.
          The default value is configured by setting the application variable 
          <em>ssl_client_options</em>.</p>
      </desc>
    </func>
    <func>
      <name>set_ssl_client_options(Options) -> ok</name>
      <fsummary>Set the SSL options for the client</fsummary>
      <type>
        <v>Options = list()</v>
      </type>
      <desc>
        <p>This function takes a list of SSL options as parameter and sets 
	it for the current process.</p>
      </desc>
    </func>
    <func>
      <name>objectkeys_gc_time() -> int() (seconds)</name>
      <fsummary>Display the Object Keys GC time value</fsummary>
      <desc>
        <p>This function returns the timeout value after which after which terminated object keys, 
          related to servers started with the configuration parameter <c>{persistent, true}</c>,
          will be removed.
          It can be configured by setting the application variable <em>objectkeys_gc_time TimeVal (seconds)</em>, 
          if it is not set it will have the default value <em>infinity</em>. </p>
        <p>Objects terminating with reason <em>normal</em> or <em>shutdown</em> are removed automatically.</p>
        <p>Note: the objectkeys_gc_time configuration parameter (TimeVal) may only range between 0 and 1000000 seconds. 
          Otherwise, the default value is used.</p>
      </desc>
    </func>
    <func>
      <name>orber_nodes() -> RetVal</name>
      <fsummary>Displays which nodes that this orber domain consist of.</fsummary>
      <type>
        <v>RetVal = [node()]</v>
      </type>
      <desc>
        <p>This function returns the list of node names that this orber 
          domain consists of. </p>
      </desc>
    </func>
    <func>
      <name>install(NodeList) -> ok</name>
      <name>install(NodeList, Options) -> ok</name>
      <fsummary>Install the Orber application</fsummary>
      <type>
        <v>NodeList = [node()]</v>
        <v>Options = [Option]</v>
        <v>Option = {install_timeout, Timeout} | {ifr_storage_type, TableType} | {nameservice_storage_type, TableType} | {initialreferences_storage_type, TableType} | {load_order, Priority}</v>
        <v>Timeout = infinity | integer()</v>
        <v>TableType = disc_copies | ram_copies</v>
        <v>Priority = integer()</v>
      </type>
      <desc>
        <p>This function installs all the necessary mnesia tables and
          load default data in some of them. If one or more Orber tables
          already exists the installation fails. The function
          <em>uninstall</em> may be used, if it is safe, i.e., no other 
          application is running Orber.</p>
        <p>Preconditions:</p>
        <list type="bulleted">
          <item>a mnesia schema must exist before the installation</item>
          <item>mnesia is running on the other nodes if the new installation 
           shall be a multi node domain</item>
        </list>
        <p>Mnesia will be started by the function if it is not already running on 
          the installation node and if it was started it will be stopped
          afterwards.</p>
        <p>The options that can be sent to the installation program is:</p>
        <list type="bulleted">
          <item><c>{install_timeout, Timeout}</c> - this timeout is how long we 
           will wait for the tables to be created. The Timeout value can be
          <em>infinity</em> or an integer number in milliseconds.
           Default is infinity.</item>
          <item><c>{ifr_storage_type, TableType}</c> - this option sets the 
           type of tables used for the interface repository.
           The TableType can be disc_copies or ram_copies. Default is 
           disc_copies.</item>
          <item><c>{initialreferences_storage_type, TableType}</c> - this option 
           sets the type of table used for storing initial references.
           The TableType can be disc_copies or ram_copies. Default is 
           ram_copies.</item>
          <item><c>{nameservice_storage_type, TableType}</c> - the default
           behavior of Orber is to install the NameService as ram_copies.
           This option makes it possible to change this to disc_copies. But
           the user should be aware of that if a node is restarted, all
           local object references stored in the NameService is not valid.
           Hence, you cannot switch to disc_copies and expect exactly the same
           behavior as before.</item>
          <item><c>{load_order, Priority}</c> - per default the priority is set to 0.
           Using this option it will change the priority of in which order
           Mnesia will load Orber internal tables. For more information,
           consult the Mnesia documentation.</item>
        </list>
      </desc>
    </func>
    <func>
      <name>uninstall() -> ok</name>
      <fsummary>Uninstall the Orber application</fsummary>
      <desc>
        <p>This function stops the Orber application, terminates all server
          objects and removes all Orber related mnesia tables.</p>
        <p>Note: Since other applications may be running on the same node
          using mnesia <em>uninstall</em> will not stop the mnesia application.</p>
      </desc>
    </func>
    <func>
      <name>add_node(Node, Options) -> RetVal</name>
      <fsummary>Add a new node to a group of Orber nodes.</fsummary>
      <type>
        <v>Node = node()</v>
        <v>Options = IFRStorageType | [KeyValue] </v>
        <v>IFRStorageType = StorageType</v>
        <v>StorageType = disc_copies | ram_copies</v>
        <v>KeyValue = {ifr_storage_type, StorageType} |  {initialreferences_storage_type, StorageType} |  {nameservice_storage_type, StorageType} |  {type, Type} </v>
        <v>Type = temporary | permanent</v>
        <v>RetVal = ok | exit()</v>
      </type>
      <desc>
        <p>This function add given node to a existing Orber node group and starts
          Orber on the new node. <c>orber:add_node</c> is called from a member in the Orber
          node group.</p>
        <p>Preconditions for new node:</p>
        <list type="bulleted">
          <item>Erlang started on the new node using the option <c>-mnesia extra_db_nodes</c>, e.g.,
          <c>erl -sname new_node_name -mnesia extra_db_nodes ConnectToNodes_List</c></item>
          <item>The new node's <c>domain</c> name is the same for the nodes we want to connect to.</item>
          <item>Mnesia is running on the new node (no new schema created).</item>
          <item>If the new node will use <c>disc_copies</c> the schema type must be changed using:
          <c>mnesia:change_table_copy_type(schema, node(), disc_copies).</c></item>
        </list>
        <p>Orber will be started by the function on the new node.</p>
        <p>Fails if:</p>
        <list type="bulleted">
          <item>Orber already installed on given node.</item>
          <item>Mnesia not started as described above on the new node.</item>
          <item>Impossible to copy data in Mnesia tables to the new node.</item>
          <item>Not able to start Orber on the new node, due to, for example, the 
          <c>iiop_port</c> is already in use.</item>
        </list>
        <p>The function do not remove already copied tables after a failure.
          Use <c>orber:remove_node</c> to remove these tables.</p>
      </desc>
    </func>
    <func>
      <name>remove_node(Node) -> RetVal</name>
      <fsummary>Removes a node from a group of Orber nodes.</fsummary>
      <type>
        <v>Node = node()</v>
        <v>RetVal = ok | exit()</v>
      </type>
      <desc>
        <p>This function removes given node from a Orber node group. The Mnesia
          application is not stopped.</p>
      </desc>
    </func>
    <func>
      <name>configure(Key, Value) -> ok | {'EXIT', Reason}</name>
      <fsummary>Change Orber configuration.</fsummary>
      <type>
        <v>Key = orbDefaultInitRef | orbInitRef | giop_version | iiop_timeout | iiop_connection_timeout | iiop_setup_connection_timeout | iiop_in_connection_timeout | objectkeys_gc_time | orber_debug_level</v>
        <v>Value = allowed value associated with the given key</v>
      </type>
      <desc>
        <p>This function allows the user to configure Orber in, for example,
          an Erlang shell. It is possible to invoke <c>configure</c> at any time
          the keys specified above.</p>
        <p>Any other key must be set before installing and starting Orber.</p>
        <p>Trying to change the configuration in any other way is <em>NOT</em>
          allowed since it may affect the behavior of Orber.</p>
        <p>For more information regarding allowed values, see
          <seealso marker="ch_install#config">configuration settings</seealso>
          in the User's Guide.</p>
        <p></p>
        <note>
          <p>Configuring the IIOP timeout values will not affect already
            existing connections. If you want a guaranteed uniform behavior, you
            must set these parameters from the start.</p>
        </note>
      </desc>
    </func>
  </funcs>
  
</erlref>