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Systems Management: Common Management Facilities (XCMF)
Copyright © 1997 The Open Group
Introduction
Overview
The Systems Management Reference Model (see reference XRM)
consists of
3 basic components:
-
Managers
which implement Management Tasks and other composite management functions.
-
Managed Objects
which encapsulate resources. Resources are the entities within a system or
network of systems that require management.
-
Services
which provide the System Management (XSM) Support Environment. The
XSM Support Environment consists of the capabilities and interfaces that
are necessary to support the other components of the Reference Model.
Management Facilities are a category of services
which have been specialized for
XSM distributed systems management. This specification defines a set of
management facilities that supplement the
Object Management Group's (OMG) Object
Model so that it supports the System Management Reference Model.
The Systems Management Reference Model (see reference XRM)
provides a complete description of the mapping to the OMG Object Model.
Relationship to the OMG Object Model
The OMG has developed a conceptual model, known as the core object
model, and a reference architecture upon which applications can be
constructed (see references OMAG and OMGOM).
The OMG OMA defines the
composition of objects and their interfaces.
A fundamental architecture of the OMA is the Common Object Request
Broker Architecture (see reference CORBA) that specifies a framework
for transparent communication between application objects. The
Object Request Broker (ORB), a key component of this architecture,
provides the mechanisms for issuing requests to objects and returning
responses.
In addition to CORBA, the OMG has also published a set of Object
Services that are common to a wide range of application domains.
The first set of these services (see reference COS Volume 1) includes:
-
Life Cycle Services
-
Naming Services
-
Event Services
Life Cycle services define interfaces for creating, deleting, moving,
and copying objects. Naming Services specify interfaces for binding
and resolving names. The Event Services provides mechanisms for
decoupled communication between objects, supporting both a push and
a pull model of communication.
In addition to these services, additional activity is underway in
the OMG to adopt specifications for Concurrency
Services, Externalization Services,
Persistent Storage Services, Relationship Services, Transaction
Services, Time Services, and Security Services. Work is also coming
to completion on a Licensing Service, a Properties Service, and a
Query Service.
It is the implementation of the OMG architectures and Object Services
that constitute an
OMG environment.
This environment provides much
of the necessary infrastructure for supporting distributed system
management.
Scope of this Specification
This specification presents a set of management services that integrate with
the OMG environment and provide extended services specifically for the
distributed systems management. These services, in conjunction with the
OMG environment, are fundamental to provide a framework for developing
distributed systems management applications.
The management facilities specified assumes an
OMG CORBA 1.2-compliant
ORB and a compliant implementation of the
Common Object Services (see reference COS Volume 1).
This implies the management facilities described in this specification
may use types and interfaces defined in OMG standard header
files (for example,
<orb.idl>).
The components addressed in this specification are those
focused on the management
of policy-driven objects including the mechanisms and facilities that enable
the establishment and enforcement of policy on these objects.
The Reference Model is used in
Systems Management Framework Components
.
to illustrate the focus of this specification. The Object Request Broker and
Object Services discussed in this specification are drawn from the OMG
environment.
Figure: Systems Management Framework Components
The systems management application domain is a vertical application market
with specialized requirements. The work OMG is performing at the ORB and
Object Services level is common across many, if not most, application spaces.
Systems management requirements exist today and a considerable industry is
beginning to build applications in this area. Thus, there is a need to
standardize interfaces for systems management. This specification does
not supersede the OMG Object Services. Rather, it complements the OMG
Object Services by defining interfaces that are fundamental for developing
distributed system administration applications.
This specification also fully backs application portability and
internationalization objectives.
In areas where relevant
standards have been identified (see referenced documents),
these standards are used. Examples are the
Portability Guide, Issues 3 and 4 (see references to XPG
documents, and to reference Internationalization Guide).
Adhering to these specifications is critical to all implementations and the
interfaces for a system administration framework must enable the use and
accommodation of these specifications.
Components Not Addressed
This section outlines a set of application development issues that are not
addressed in this specification, but that must be addressed during the
development of system administration applications.
Security
Providing a robust and flexible security service is crucial for the
development of distributed management applications. Providing such a
service in a heterogeneous and distributed environment is a very complex
undertaking. The OMG is currently developing a Security service for the
CORBA environment. The Open Group
is tracking its progress closely and hopes to
build upon this service. Because of the complexity of defining the service
and the ongoing working in the OMG, a Security service is beyond the
scope of this Specification.
Graphical User Interface/Desktop
There are other standards groups and industry consortia working to define a
common desktop environment, including the graphical user interface (GUI)
technology. Proposing a particular approach to this effort through a parallel
process is inappropriate. While the GUI and desktop is critical to the
success of individual administration applications, it is not fundamental for
the development of distributed management applications.
Application Specific Resource Interfaces
This specification details a set of interfaces for management facilities that
enables the development of distributed management applications. These
applications will include policy-driven objects that encapsulate managed
resources. The definition of the interfaces to the objects to encapsulate
managed resources is outside the scope of this specification.
Interoperability Issues
Interoperability is key to building distributed systems management
applications. Distributed systems management applications using the
OMG environment requires interoperability at two distinct levels:
-
ORB-to-ORB
Interoperability at this level requires that ORBs developed by two
independent entities are able to communicate with each other. The method
requests dispatched by one ORB are able to be received and understood by
another.
ORB-to-ORB interoperability is addressed by OMG's CORBA 2.0 Specification.
-
Object Interfaces
Interoperability of object interfaces requires that a objects developed in
one OMG environment have an interface (or subset of inherited interfaces)
that is common to another environment. That is, an object developed by one
vendor may make a request on an object developed by a different vendor
through a known interface. This is true for both compiled, executable
applications development as well as for implementations of policy by the
system administrators.
Object Interfaces interoperability is being
addressed by the OMG in the Object Services. These object service
interface specifications address a very general class of distributed,
object-oriented applications. The management services interfaces detailed
in this specification define interfaces for the development of system
administration applications. Thus, this specification provides interfaces
and command line interface equivalents that are specific to developing
interoperable system administration applications integrated with the
OMG environment.
Interoperable object interfaces also allow objects to be portable
across different implementations of the OMG environment.
Future Directions
The facilities specified in this specification provide only a subset of all the
facilities necessary to build portable and interoperable management
applications. As CORBA based management frameworks become more prevalent
in the industry, more management facilities will be developed and deployed.
The developers of this Specification
recognize this fact and hence expect to identify and standardize
additional management facilities in future.
Some number of facilities and language bindings were identified as important
during the development of this Specification, but because of
resource limitations
are not included in this Specification. Some of the facilities
identified were such things as process management, scheduling,
event management, and a Perl language binding.
These facilities are excellent candidates for
inclusion in a future volume of management facilities.
However, this vision should in no way be interpreted as
limiting the breadth of future submissions in this area.
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