Overview of Pegasus An Open-Source WBEM implementation

1
Overview ofPegasusAn Open-SourceWBEM
implementation

• 19 September 2001
• Karl Schopmeyer (k.schopmeyer_at_opengroup.org)

www.opengroup.org/pegasus
Version 1.0
2
Agenda

• Overview -What (and why)is Pegasus?
• What is CIM / WBEM
• The Pegasus Environment
• The Pegasus Software Architecture
• Pegasus Status Today
• The Pegasus Project
• Future Directions

3
1. Overview
4
What is Pegasus?

• Pegasus is an open-source reference
  implementation of the DMTF WBEM specifications
• Pegasus is a work project of the TOG Enterprise
  Management Forum
• Pegasus is a platform for building application
  management
• Pegasus is a function-rich, production-quality
  open-source implementation designed to be used in
  high volume server implementations.

Pegasus is real today and will be in systems next
year
5
Why Produce Pegasus?

• Demonstrate manageability concepts.
• Provide additional standards for WBEM
• Provide a working implementation of WBEM
  technologies
• Provide an effective modular implementation
• Support other Open Group manageability standards
• Base Platform for Open Group Application
  management Projects
• Help make WBEM real

• Initiated in 2000 by the Open Group in
  collaboration with
• BMC Software
• IBM
• Tivoli Systems

6
Key Pegasus Objectives
MIT License
Open Source
Standards Based
DMTF WBEM
Pegasus
Continuity
Portable
C and portable Libraries
Continuing Project
Modular And Extensible
Efficient And Lightweight
Production Quality
C Code Base
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Pegasus Working Group Philosophy

• Manageability not management
• The working groups objective is not to manage
  systems but to make them manageable by promoting
  a standard instrumentation environment
• The actual management of systems is left to
  systems management vendors
• No standards without implementation
• The process of implementation provides a rigorous
  process for testing the validity of standards
• Therefore all standards must be validated by
  implementation

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Pegasus is Open Source

• Code and documentation freely available
• Open Group and Source Forge
• MIT source license
• Open to contributions
• No commitment to Open Group to use code

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Pegasus is Portable

• Designed for multi-platform, multi-OS,
  multi-compiler implementation
• Platforms ported today
• UNIX (AIX, HPUX, Compaq Tru64, Solaris)
• Linux
• Windows Platforms (NT, 2000, 9x)
• Compaq Himalaya (Tandem)

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Efficient and Lightweight

• Core written in C
• Designed for execution efficiency
• Designed to be production-quality solution

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Pegasus is Standards Based

• Based on DMTF CIM and CIM-XML specifications
• Open Group is active partner in DMTF
• Growth through participation in specification
  growth
• Commitment to continue DMTF compliance

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Pegasus is Modular and Extensible

• Minimize core object broker.
• Maximize extensibility through plug-in components
• Component types
• Providers
• Provider interfaces
• Clients
• Repositories (additional repository handlers)
• Manageability service extensions
• Protocol Adapters
• Modules (extend and modify core functions)

Modularity is key to doing parallel development
and allowto extensibility
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Project for Continued Development

• WBEM will continue to develop functionality and
  standards
• Open Group will develop application management
  partly around Pegasus
• Pegasus Development will continue beyond current
  versions
• Integrate contributions
• Add basic new functionality
• Etc.

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2. WBEM and CIM Standards
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The Management Standards Groups

• DMTF
• DMI
• CIM / WBEM
• The Open Group
• Unix Management Standards
• Application Management Standards
• CIM WBEM
• IETF
• SNMP
• TMF
• CMIP
• ????

SNMP
CMIP
DMI
WBEM
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WBEM Architectures
WBEM
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What it is CIM?

• Implementation neutral schema for describing
  overall management information
• Facilitates the common understanding of
  management data across different management
  systems
• Facilitates the integration of management
  information from different sources
• A data model not an implementation
• MOF syntax supports sharing information across
  management systems
• Models for both instrumentation and management

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DMTF WBEM Components
CIM Specification V2
Interoperability Specifications

• CIM Operations over HTTP
• CIM XML

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Web-based Enterprise Management (WBEM)

• Information Model
• CIM Schema (Core, System,)
• Communication Model
• CIM Operations over HTTP
• Transport Encoding
• Cim-xml CIM/XML mapping
• Event Model
• CIM indications (new in 2.5)
• CIM Object Manager (CIMOM)
• Operation Routing
• Result Aggregation
• Repository
• Class and Instance Persistence
• Resource Providers
• Instrumentation subagents

Management Applications
CIM Client
cim-xml Transport
CIM Object Manager
Schema
CIM Server
Resource Providers
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Common Information Model

• Defines the Schema used to represent real-world
  objects being managed
• Object oriented paradigm
• CIM Specification
• Meta model, high level concepts, and definition
  language (MOF)
• CIM Schema
• Core and Common Model

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WBEM Architecture Components
CIM Clients
CIM Listeners
CIM Operation Requests
CIM Operation Responses
CIM Indications
CIM Server
MOF
Providers
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Interoperability Characteristics

• XML encoding
• Definition for each operation
• HTTP Transport
• HTTP 1.0 and 1.1
• Common Operations Semantics
• Data
• Meta data
• Queries?
• Methods

CIM Client
CIM Server
Managed Resources
Managed Resources
Managed Resources
Managed Resources
Managed Resources
Managed Resources
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Managed Object Format (MOF)
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CIM Operations

• Intrinsic Operations
• Create, Modify, Delete
• Qualifiers
• Classes
• Instances
• Properties
• Invoke Query
• Extrinsic Operations
• Execute Methods

CIM Clients
CIM Operation Requests
CIM Operation Responses
CIM Server
ltinstancegt GetInstance ( IN
ltinstanceNamegt InstanceName,
IN,OPTIONAL boolean LocalOnly true,
IN,OPTIONAL boolean IncludeQualifiers false,
IN,OPTIONAL boolean IncludeClassOrigin
false, IN,OPTIONAL,NULL string
PropertyList NULL )
Providers
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CIM Indications

• Indication Types
• Process Indications
• External Events
• Lifecycle indications
• Changes to CIM Objects

CIM Listener
CIM Client
SNMP
4
1
Export Indications
Subscription
Indication Handler
Indication Handler
Indication Subscription Object
CIM Server
CIM Indication Handler Object
CIM Filter Object
Filter
Produce Indications Based on Filter
2
Indication Provider
Indication Provider
3
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Query Language - WQL

• SQL based Query Language
• Used in
• CIM Indication Filters
• CIM Queries (CIM Operation)
• 4 levels of Language
• 1 Simple queries from single tables
• 2 Adds DELETE INSERT UPDATE
• 3 Add complex expressions and specific data
  constructs
• 4 Add Joins, etc.

Subset of SQL supports queries in the form
SELECT ltrow setgt FROM lttable listgt
WHERE ltselection expressiongt
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2. The Pegasus Environment
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Major Components
Client
Many Clients Management Applications
Client
CIM Clients
CIM-XML
Repository
CIM Object Manager
Client
Client
Many Providers per CIMOM
CIM Providers
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Key Interoperability Interfaces
Management System
Enterprise Management Console

• Manageability to Manager
• Multiple management systems
• Common open manageability

CIM Object Manager

• Object Manager / Providers
• Multiple Providers
• Encourage common providers

CIM Providers

• Provider / Resource Interface
• Protect Applications
• Make application management easy

Application
Application
Application
Application
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CIMOM Capabilities

• Respond to Operations defined in CIM Operations
  spec.
• Create, Modify, Delete operations on
• Class, Instance, Property, Qualifier
• Handle Provider Registration
• Forward Requests to Providers, repositories, etc.
• Read/Write access to Management Information
• Maintain Class/Instance Information
• Traversal of Associations
• Use of WBEM Query Language
• Syntax/Semantic checking (with Qualifiers)
• Available Implementations
• Microsoft (in Windows2000), Sun WBEM SDK, SNIA,
  Open Group Pegasus,

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Pathways of Communication
Client
Client
CIM Clients
CIM Repository
CIM Object Manager
Client
Client
CIM Providers
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Component Location

• A component may be located in one of three places
  with respect to the CIM Server.
• In-process.
• Local out-of-process (on the same machine).
• Remote out-of-process (on another machine).
• For example, a provider may be in-process, local,
  or remote.

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Component Location in Pegasus
Today

• Components could potentially communicate the
  following mechanisms
• CIM/HTTP (remote).
• Proprietary TCP-based protocol (remote).
• Direct call (in process).
• Shared memory (local).
• Named pipes (local).

Future
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The Pegasus CIMOM
Client
Client
CIM Clients
Repository
CIM Object Manager (CIMOM)
Client
Client
CIM Providers
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Operations Routing

• Class Operations
• Routed to the Class Repository
• Instance Operations
• To Provider if Provider Qualifier exists
• To Instance repository if no Provider
• Instance routing at Class Level Today
• Issues Routing at instance level

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Operation Routing
Client

• Class Operations
• Routed to the Repository

Client
CIM Clients
Repository
CIM Object Manager
Client
Client
CIM Providers
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Operation Routing
Client

• Instance Operations Routing
• Routing By Class
• To Provider if Qualifier Defined
• Default is to Instnace Repository

Client
CIM Clients
Repository
CIM Object Manager

• Future
• Routing by Instance
• Definition by provider registration

Client
Client
CIM Providers
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Indication Routing
Client

• Indication routing

Client
Client
Client
CIM Listener
CIM Clients
Subscriptons
Handler
Handler
Handler
Repository
CIM Object Manager
Indications
Client
Client
CIM Providers
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Request Lifecycle
Outgoing Response
Incoming Request
1. Receive TCP Message
Channel
Channel
8. Transmit TCP Message
Protocol
7. Form HTTP Response
2. Process HTTP Request
Protocol
Encodings
Encodings
3. Decode XML
6. Encode to XML
Aggregator
Repository
5. Aggregate Results
Dispatcher
4. Dispatch Request
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Pegasus CIMOM Architecture Components
Cim-xml Protocol Adapter

• CIMOM
• Support
• Services
• Start
• Stop
• Log
• Statistics

Decoder/coder
Repository Interface
Indication Handlers
Delegators
Operations Dispatcher
Operations Aggregator
Indication Processor
Provider Manager
. . .
Provider Interface C
Provider Interface C
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Modularity and Extensibility

• Providers
• Grow with DMTF provider concepts
• Provider Interfaces
• Protocol Adapters (connectors)
• Client - xml-cim today (Soap, etc. in future)
• Provider, service, repository, etc.
• Modules
• Modularize core so it can be extended and
  modified through attachable modules
• Manageability Service Extensions
• Think super providers

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Building A Modular Manageability Environmnent
Core Object Manager
Connector
Connector
. . .
Provider
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Provider Interoperability

• In the classical architecture, interoperability
  is only supported between the client and server.
• In addition, the Pegasus architecture aims to
  support provider/server interoperability.
• Goal
• Write a provider once and run it under any CIM
  server implementation.
• Provider/Server Interoperability
• Participating in efforts to standardize the
  Provider/Server protocol.
• Proposing provider API standards.
• Writing adapters enabling Pegasus providers to
  run under other CIM servers.
• Adapters enabling other providers to run under
  Pegasus

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Flexible Provider Interfaces

• SUN WBEM Provider Interface
• Java based
• Classes, etc. similar to Pegasus
• C Provider Interface
• Many Providers written in C
• We will support multiple provider interfaces and
  language bindings.
• Perl, Scripting, etc.

CIM Object Manager
Interface Adapter
Interface Adapter
Interface Adapter
Providers
Providers
Providers
Providers
Providers
Providers
Providers
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In-Process and Out-of-process Providers

• Today Pegasus based on shared Library Providers
• Extend to
• Internal Providers
• IPC based Providers
• Providers in Remotes systems
• Objectives
• Write Provider once and compile/link for
  different environments
• Technique
• Use connectors as basis for provider/CIMOM
  communication
• Issues
• Security, discovery

46
Pegasus Modules

• The core server functions are organized into
  loadable modules.
• Standard APIs are defined for each module.
• Alternative implementations can be provided later
  without recompiling the Pegasus server.

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Manageability Service Extensions

• Super Providers
• Access to the Core Broker

• Examples
• Indication Management service.
• Query engine service.
• Class repository service.
• Instance repository service.

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Connectors (Protocol Adapters)

• Functions
• Adapt to different protocols
• Characteristics
• Protocol
• Encoding
• Security
• Discovery
• Examples
• Xml-CIM
• Local Protocols
• Soap
• WMI
• Corba environment interface

Xml-cim Client
Soap Client
Xml-cim Connector
Soap Connector
External Corba Environment
Pegasus Core
Corba Connector
Pegasus Provider
Connector
Remote Provider
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Pegasus Manageability Environment
Object Browser Editor
Client SDK
Service extensions
Consumers Gateways Apps
XML/CIM Connector
Security

• CIM Object Broker Broker)
• Provider Registration
• Service Registration
• Request Routing

Broker
Queuing
Class Repository
Security
Events
MOF Compiler
Instance Repository
Provider SDK
ARM Provider
. . .
Provider SDK
Providers
Remote Provider
Interface For Spec
Resource
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Programming Language Support

• The Pegasus core is implemented in C and hence
  client and provider interface are provided for
  C.
• An integrated JVM is planned to allow providers
  to be developed in Java.
• Of course it is possible to use existing Java
  clients to interact with the Pegasus CIMOM.

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CIM Objects in C

• CIMClass
• CIMInstance
• CIMProperty
• CIMMethod
• CIMParameter
• CIMQualifierDecl
• CIMQualifier

52
Class Declaration Example

• Consider the following MOF class declaration
• class Alarm
• key
• uint64 id
• string message none
• This class is defined in C as follows
• CIMClass alarmClass(Alarm)
• CIMProperty id(id, Uint32(0))
• id.addQualifier(CIMQualifier(key, true))
• CIMProperty message(message, none)
• alarmClass.addProperty(id)
• alarmClass.addProperty(message)
• Or more succinctly like this
• CIMClass alarmClass(Alarm)
• alarmClass
• .addProperty(CIMProperty(id, Uint32(0))
• .addQualifier(CIMQualifier(key, true)))

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Property Iteration Example

• The properties of a class may be iterated like
  this
• CIMClass c
• for (Uint32 i 0, n c.getPropertyCount()
• i lt n i)
• CIMProperty p c.getProperty(i)

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The Client Interface

• Interfaces set by WBEM Specs.
• Local and Remote
• Future Add other protocols

Client
Client
CIM Clients
Repository
CIM Server

• A C interface for interacting with the Pegasus
  Server (or any CIM Server).
• Uses CIM/HTTP (cim-xml) to communicate.
• Provides a method for each CIM operation defined
  in the CIM Operations over DMTF HTTP, V1.0
  specification.

Client
Client
CIM Providers
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The CIM Operations

• GetClass
• GetInstance
• DeleteClass
• DeleteInstance
• CreateClass
• CreateInstance
• ModifyClass
• ModifyInstance
• EnumerateClasses
• EnumerateClassNames
• EnumerateInstances
• EnumerateInstanceNames
• ExecQuery

• Associators
• AssociatorNames
• References
• ReferenceNames
• GetProperty
• SetProperty
• GetQualifier
• SetQualifier
• InvokeMethod

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CIM Operation Example
ltinstancegt GetInstance ( IN
ltinstanceNamegt InstanceName,
IN,OPTIONAL boolean LocalOnly true,
IN,OPTIONAL boolean IncludeQualifiers false,
IN,OPTIONAL boolean IncludeClassOrigin
false, IN,OPTIONAL,NULL string
PropertyList NULL )
CIM Operations Specification
virtual CIMInstance getInstance( const
String nameSpace, const CIMReference
instanceName, Boolean localOnly true,
Boolean includeQualifiers false, Boolean
includeClassOrigin false, const
ArrayltStringgt propertyList NULL_PROPERTY_L
IST)
Pegasus Class Method
57
The Provider Interface
Client

• Many Providers, few CIMOMs
• Providers dynamically added, upgraded, deleted in
  the environment

Client
CIM Clients
Repository
CIM Server

• Defined by the C CIMProvider class.
• Method for each CIM operation in the CIM
  Operations over HTTP, V1.0 specification.
• Methods for Provider control (start, stop,
  status, etc.)
• CIMProvider is a base provider interface (more
  refined provider interfaces are being developed).

Client
Client
CIM Providers
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CIMProvider Methods

• getClass()
• getInstance()
• deleteClass()
• deleteInstance()
• createClass()
• createInstance()
• modifyClass()
• modifyInstance()
• enumerateClasses()
• enumerateClassNames()
• enumerateInstances()
• enumerateInstanceNames()
• execQuery()

• Associators()
• associatorNames()
• references()
• referenceNames()
• getProperty()
• setProperty()
• getQualifier()
• setQualifier()
• invokeMethod()

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Example of modifyInstance() Method

• The provider developer derives from CIMProvider
  and overrides the modifyInstance() method.
• class MyProvider public CIMProvider
• virtual void MyProvidermodifyInstance(
• const String nameSpace,
• CIMInstance modifiedInstance)
• // Modify the instance here!

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Provider Registration and Loading

• Providers are configured as dynamic libraries
  with an entry point function for creating the
  provider instance.
• The provider() qualifier is placed on the
  corresponding class in the repository (this
  qualifier specifies the library name containing
  the provider implementation) .
• The provider is loaded on demand (when instances
  of that class are requested).

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Refined Provider Interfaces

• CIM operations assigned to different types of
  providers
• Instance provider
• Method provider
• Query provider
• Event provider
• Association provider
• Provider Interface Managers map the base provider
  interface onto one or more other provider
  interfaces. This scheme may be used to
• Refine the base provider interface into several
  provider interfaces (as mentioned above).
• Map the provider interface onto other language
  provider interfaces (e.g., Java, Perl, Tcl).

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Provider Proposals

• Interoperability with SUN Wbem providers proposal
• We are extending other interoperability ideas

Pegasus CIMOM
SUN WBEM CIMOM
Microsoft CIMOM
Pegasus Providers
SUN WBEM Providers
Microsoft WMI Providers
63
4. The Pegasus Implementation Today And Tomorrow
64
Status Today

• Version 1 complete (Beta Level Code)
• Includes
• CIMOM including
• HTTP Server and CIM-xml Protocol
• Provider interfaces and dispatch
• Repository with Instances, Classes, Associations
• C CIM Object Model representation
• Admin and support functions
• MOF Compiler
• Client Interface and test clients
• Test providers and beginning of some real
  providers
• Integrated unit and client server tests
  (regression)
• Version 2 in process
• Add CIM Indications
• Threading, message base, etc.
• Security
• Production Functions

65
The Components Today
Browsing Client
Test Clients
Compiler
Instance Repository
Pegasus CIM Object Manager
Class Repository
C Interface Adapter
C Interface Adapter
C Providers
66
Planned Extensions

• CIMOM Functions
• Security
• Indications
• Threading
• Async CIM Operations APIs
• More Modularity
• Enhance Service Configuration
• Expanding Provider Characteristics
• Out-of-Process Providers
• WBEM Functions
• Discovery
• CIMOM Object Manager Characteristics
• Provider Registration and Operations

• Clients
• Object Browser
• Test Clients
• Protocol Adapters
• Add protocol Adapters
• Providers
• Test
• Sample Implementations
• Java Module Interface
• Platforms
• Easier portability
• More platforms

67
Phase 2 Priority tasks

• Threaded Model
• Indications Support
• CIM Object Manager Capabilities Reporting
• Discovery
• Additional Modularization
• Security
• Message based model

68
Summary - Key Characteristics

• Open source
• Available Today
• Portable
• Designed to build and run on wide variety of
  platforms
• C core
• C CIM Objects
• C Operation/Provider/Service/Repository
  interfaces
• Modular and extensible
• Modular components to extend the core
• Manageability service extensions to extend
  functionality
• Light weight

69
5. The Pegasus Project
70
Overview of the Project

• Active project of Enterprise Management Forum of
  the Open Group
• Producing
• Pegasus open-source Implementation
• Core, clients, providers, repositories
• SDKs (Provider and Client)
• Documentation for use and development
• Specifications for major Interfaces
• Continue support and growth of Pegasus
• Portability
• New functions
• New Standards requirements
• New Providers
• Tools

Pegasus Is a continuing project, not a one-shot
development
71
Pegasus Status Today

• Phase 1 of 3 Phases
• Version 1.0 Available
• Source Code available today
• Preliminary documentation available
• Multiple users evaluating today
• Tested on the platforms defined

72
Pegasus Project Phases

• Phase 1 (July 2001)
• Goals
• Model Validation
• Client and Provider development
• Basic Environment
• Core model
• Cim-xml Operations
• Class and instance repositories
• Providers

• Phase 2 (September)
• Goals
• Production Environment
• Additions
• Threading
• Configuration
• Security
• Service Extensions
• Indications
• Discovery
• Phase 3
• Remote Providers
• Other extensions including other Language
  Interfaces (ex. Java connector)

73
Participants

• BMC Software
• Compaq Computer
• Focal Point
• Hermes Softlab
• Hewlett Packard
• IBM
• SIAC
• The Open Group
• Research Institute
• Management Forum
• Tivoli

• Major Contributors
• BMC
• Compaq
• Hewlett Packard
• IBM

74
Working Together

• Open Source but coordinated
• Executive Committee directs strategy
• Single Architect
• Work from Proposals
• Agree to objectives before doing the work
• Regular, Stable Releases
• Developers style guides
• Project scheduling and planning

75
Immediate Activities

• CIMOM
• Security
• Indications
• Threading
• Providers
• Finalize interfaces
• Create Provider SDK
• Remote providers
• Growth of functionality with DMTF
• Discovery
• Provider standardization (registration,
  interfaces)
• Next generation interoperability

Pegasus will go where the contributors want it to
go
76
Pegasus and Other Manageability Projects

• AIC Application and Control
• AIC as a Pegasus Provider
• ARM Applications Response Measurement
• ARM and DMTF DAP Information as Pegasus Provider
• Other possible Providers
• JMX (Java)
• SNMP (mapping already defined)
• DMI (mapping already defined)

77
Open Source and WBEM

• Implementations
• Pegasus (The Open Group)
• SNIA (Storage Network Industry Assoc.)
• Caldera (Linux)
• Sun WBEM Services
• NOTE SNIA implementation to move to the Open
  Group in October 2001
• Working towards Commonality through a new
  Consortium WBEMSource Consortium

78
WBEMSource Consortium
Create an environment of open-source WBEM
implementations
Create a library of providers and tools

• Create common interfaces and APIs

WBEMsource
Hosted by The Open Group
Create commonality between implementations and
integrate different implementations.
Create an environment of conformance
Members Today Sun, Compaq,IBM, Tivoli, Open
Group, SNIA, Caldera, Novell, Nokia, Intel
79
6. Future Directions
80
Future Work

• Continue Pegasus Development
• Integrate Pegasus with Application Management
  standards
• Merge the environments of the SNIA and Pegasus
  CIMOMs
• Standardization and growth of Providers
• Integrated Pegasus with user needs like QOS
• Grow standards
• DMTF standards for WBEM
• Open Group standards for WBEM APIs
• Application and Service Management

81
Where will you see Pegasus

• The following is a guess
• Unix Oss
• Linux
• Several other OSs

• HOWEVER
• Pegasus is not done today
• WBEM is not done today
• It needs more support
• It needs more customer interest in WBEM
• It needs more interest and support by ISVs

82
CIMOMs - Basic Concepts

• Tool to create Management Interoperability
• Infrastructure for manageability
• Manageability interoperability
• Xml-cim today, ??? Tomorrow
• Instrumentation Interoperability
• Many providers, few CIMOMs
• Lots of applications limited numbers of
  providers

83
However

• We do not make money off of infrastructure
• If we dont have common interfaces we will not
  have interoperability.
• WBEM will be useful only when it becomes
  ubiquitous
• CIM is not Easy. Creating complete and Correct
  CIM environments is not easy
• There is a lot of work to do with a common
  environment and much more with many different
  environments

84
Creating an interoperable environment

• Creating a common interoperability environment
• Management Manageability xml-cim
• Providers APIs and protocols
• Provider building Common object implementations
• The choice
• Build a common structure with contributions
• Everybody does their own thing. (Many
  incompatible and incomplete WBEM Implentations

85
The Challenge!!!

• Can we create a common WBEM infrastructure?
• OR
• do we all go our own way?

86
Making WBEM Ubiquitous

• We are all involved.
• Suppliers
• Software/application suppliers
• End User organizations
• We will only get what we really demand

87
Where to Get More Information

• Pegasus is public and Open Source
• www.opengroup.org/pegasus
• Pegasus WEB Site
• Source Code
• Builds on Linux and Windows
• Snapshots and CVS
• Binary Release
• Documentation
• Pegasus Working Group

This presentation is on the Pegasus Site
Contributors and Users of the Code are Welcome