Last Updated: March 15, 2001
Your application can obtain and make available information about any manageable system resource by using remote instrumentation interfaces. For the purpose of this guide, these interfaces or protocols refer to industry-standard remote management interfaces. Through standardization, your information can be used by other remote management applications in a heterogeneous environment. This information is commonly used for configuration and monitoring from your remote management application, which can be running on an enterprise management console.
This guide describes three major interfaces that developers can use to instrument their resources in AIX. These interfaces are:
This guide covers the following topics:
Usually the best place to start is by taking the data and characteristics about your component and writing them out. If you start dividing things logically, some common things start to fall out in any situation. There is a managed resource or component, a device or application running on AIX that needs to be managed. There is also the need to manage this component from a remote management workstation or management console. This component would also have information associated with it that is specific to that device or application and information that needs to be configured or monitored. Because management is done over the network, an externally available protocol must be used to allow the management pieces to communicate.
The managed component can be any resource, designed for any task, as long as it has configuration information and is on an AIX system that is connected to the network. Keep in mind that a managed component could be an application running on a system that is itself a managed component. There could be one component or hundreds of components that comprise your system.
Your component will also need a remote management application. This management application will know the context of the information that your component has to configure. For your management application to make a change to your managed component, there must be an application associated with your component that is used for managing the component residing on an AIX system.
The state of the managed component and the configuration parameters are examples of management information. This information is specific to the managed component and includes any configuration parameter or process that you would want to monitor from across the network.
When you are deciding what information might be
useful to make available to the administrator, consider the following questions.
These questions are not meant to cover all possible areas that you would
need to manage, but, are provided as a guideline to help you start thinking
about the remote management needs of your component.
After you collect this set of information
for your component, it will be easier to decide which instrumentation interface
to use to make this information available. Each of the management interfaces
discussed in the guide has its strengths and weaknesses. You might have
really good reasons to pick one instrumentation interface over another.
It is rare that one interface methods will ideally suit all the information
for your component, but you can use the following chart to help you pick
the best fit for your situation.
| Characteristics needed | SNMP | LDAP | CIM |
| Data changes continuously | X | ||
| Data changes hourly | X | ||
| Data changes daily or less | X | X | X |
| Data has many interrelationships | X | X | |
| Data associates lists to other lists | X | X | |
| Data shared across many systems | X | ||
| Industry standard format | X | X | |
| Currently in use | Everywhere | Some | Very Few |
The component configuration and monitoring information will need to be formatted into a Management Information Base (MIB) extension. There is only one MIB database per system. Different systems on the network support different areas of the MIB. The term MIBs is used to describe several MIB extensions, or logical areas of a MIB that describe a specific resource or system. For more information on MIB design, see the appendixes of this guide.
After the MIB extension is defined, you can write
a special SNMP agent called a sub-agent. The sub-agent will only
support queries for data objects represented in the MIB extension that
you define. The main SNMP agent in AIX supports dynamic distributed agent
APIs. These APIs allow the system administrator to dynamically add,
delete, or replace sets of management objects in the local Management Information
Base, without requiring a recompile of the main SNMP agent. The supported
APIs are DPI and SMUX. DPI is newer and more robust than SMUX, but SMUX
is provided for existing SMUX-based sub-agents. If you will be developing
a new sub-agent on AIX, use the DPI interface. For more information on
SMUX and DPI, see the RFC links in Appendix A.
The Distributed Management Task Force (DMTF) is the standards body that defines the CIM data model. The data model is object-oriented and allows for complex multidimensional relationships between objects. The data model is represented in CIM schema and expressed in a Managed Object File (MOF). You can read more about the schema and its design at the DMTF web site listed in Appendix A or in the book listed in Appendix B.
For AIX, CIM objects are made available through
attachment to a CIM Object Manager (CIMOM). To make you component data
available as XML objects through the CIMOM, you need to write a provider.
A provider is code that supports only the CIM extensions that are
meaningful for your component. The provider API is used to attach and register
your component objects. More information can be obtained from the books
and links listed in the appendixes of this guide.
LDAP information is stored in an object-oriented
tree structure called a schema. The stored data is not intended
to be changed frequently. Access to storage and retrieval of the information
objects is done through the LDAP API. More information on this API can
be obtained from the books and links in the appendixes of this guide.
Technical University of Braunschweig - Excellent
source for SNMPv3 information
http://www.ibr.cs.tu-bs.de/ietf/snmpv3/
Architecture overviews
http://www.rad.com/networks/1995/snmp/snmp.htm
http://www.ddri.com/Doc/SNMP_Overview.html
You can access the following IETF RFCs by substituting the RFC number for the XXXX in the following URL:
http://www.ietf.org/rfc/rfcXXXX.txt
RFC 1155 - Structure and Identification of Management
Information for TCP/IP based internets.
RFC 1156 - Management Information Base Network
Management of TCP/IP based internets
RFC 1157 - A Simple Network Management Protocol
(SNMP)
RFC 1158 - Management Information Base Network
Management of TCP/IP based internets: MIB-II
RFC 1187 - Bulk Table Retrieval with the SNMP
RFC 1212 - Concise MIB Definitions
RFC 1213 - Management Information Base for Network
Management of TCP/IP-based internets: MIB-II
RFC 1215 - A Convention for Defining Traps for
use with the SNMP
RFC 1227 - SNMP MUX Protocol and MIB
RFC 1228 - SNMP-DPI: Simple Network Management
Protocol Distributed Program Interface
RFC 1303 - A Convention for Describing SNMP-Based
Agents
RFC 1592 - Simple Network Management Protocol
Distributed Protocol Interface Version 2.0
RFC 1905 - Protocol Operations for Version 2
of the Simple Network Management Protocol (SNMPv2)
RFC 1906 - Transport Mappings for Version 2 of
the Simple Network Management Protocol (SNMPv2)
RFC 1907 - Management Information Base for Version
2 of the Simple Network Management Protocol (SNMPv2)
RFC 2570 - Introduction to Version 3 of the Internet-standard
Network Management Framework
RFC 2571 - An Architecture for Describing SNMP
Management Frameworks
RFC 2572 - Message Processing and Dispatching
for the Simple Network Management Protocol (SNMP)
RFC 2573 - SNMP Applications
RFC 2574 - User-based Security Model (USM) for
version 3 of the Simple Network Management Protocol (SNMPv3)
RFC 2575 - View-based Access Control Model (VACM)
for the Simple Network Management Protocol (SNMP)
RFC 2576 - Coexistence between Version 1, Version
2, and Version 3 of the Internet-standard Network Management Framework
Storage Network Industry Association Java-based
CIMOM
http://www.snia.org/English/Resources/Code/CIM_OM.html
University of Michigan - Historical information
and FAQs
http://www.umich.edu/~dirsvcs/ldap/
LDAP Tutorials and links
http://www.kingsmountain.com/ldapRoadmap.shtml
Background information and links
http://people.netscape.com/bjm/whyLDAP.html
Open source LDAP effort
http://www.OpenLDAP.org/
You can access the following IETF RFCs by substituting the RFC number for the XXXX in the following URL:
http://www.ietf.org/rfc/rfcXXXX.txt
RFC 1777 - Lightweight Directory Access Protocol
RFC 1778 - The String Representation of Standard
Attribute Syntaxes,
The Simple Book: An Introduction to Management
of TCP/IP-based Internets (Second Edition)
Author: Marshall T. Rose
ISBN 0131772546
A Practical Guide to SNMPv3 and Network Management
Author: Dave Zeltserman
ISBN 0130214531
SNMP, SNMPv2, SNMPv3 and RMON 1 and 2
Author: William Stallings
ISBN 0201485346
SNMP, SNMPv2 and CMIP: The Practical Guide to
Network Management Standards
Author: William Stallings
ISBN 0201633310
Network Management: A Practical Perspective
Author: Allan Leinwand & Karen Fang
ISBN 0201527715
Managing Internetworks with SNMP
Author: Mark A. Miller, P.E.
ISBN 1558513043
Total SNMP
Author: Sean Harnedy
ISBN 1878956337
How to Manage Your Network using SNMP
Author: Marshall T. Rose & Keith McCloghrie
ISBN 0131415174
SNMP: A Guide to Network Management
Author: Sidnie Feit
ISBN 0070203598
Understanding SNMP MIBs
Author: David Perkins
ISBN: 0134377087
Programming Directory-Enabled Applications With
Lightweight Directory Access Protocol
Authors: Tim Howes, Mark Smith
ISBN: 1578700000
Big Book of Lightweight Directory Access Protocol
(LDAP) RFCs
Authors: Pete Loshin, Bill McCarthy
ISBN: 0124558437
Implementing LDAP
Author: Mark Wilcox
ISBN: 1861002211
Understanding LDAP
Author: IBM International Technical Support
Organization (IBM Redbooks)
ISBN: 0738400149
LDAP Implementation Cookbook
Author: IBM International Technical Support Organization
(IBM Redbooks)
ISBN: 0738413313
LDAP Programming: Directory Management and Integration
Author: Clayton Donley
ISBN: 1884777910
LDAP Programming with Java
Author: Rob Weltman, Tony Dahbura
ISBN: 0201657589
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