Oracle Video server, Руководство пользователя

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Oracle Media Net
System Architecture 2-17
Objects, Interfaces, and Servers
This section briefly defines terms used in a CORBA environment:
■
An object is a means of encapsulating functionality and providing a simple and
consistent interface that defines how clients can use that functionality.
■
An interface defines a named set of related operations. The description of an
object is a set of operations defined in an interface.
■
A server is a single computer process that implements one or more interfaces.
You can define the interfaces for your own objects by writing an IDL (Interface
Definition Language) file. Oracle Media Net provides an IDL compiler for creating
C programming language files from your IDL files.
Oracle Media Net also provides an IFR (interface repository) that you can load with
object interface definitions. You can then write applications that use DII (dynamic
invocation interface) to query the IFR at run time and construct requests for objects
defined there.
Scalability and Load Balancing
If demand for a server (such as an OVS service) increases, you can start additional
instances of the server to better handle it. Oracle Media Net can distribute requests
for a server across available instances to balance the load among them. If one
instance fails, Oracle Media Net can redistribute new requests across the remaining
instances.
Logging Error and Warning Messages
Oracle Media Net logs error and warning messages for the OVS system. For
example, if the OVS rejects a client connection request, messages in the log explain
why.
Logging is configurable:
■
You can configure a common event logging daemon to write messages for all
components of the OVS system to a common logfile.
■
You can run multiple event logging daemons. For example, you can configure
multiple daemons in a hierarchy so that several daemons each log messages for
a group of components and forward only the severe messages to a single
daemon. This daemon then writes to a logfile or console and alerts an
application service of only the most severe messages. You can then program the
application service to notify the administrator.