ogsa-based problem determination an use case · the open grid services architecture? extensions to...

Haifa Research Lab.

Nov. 24, 2003

OGSA-based Problem DeterminationAn Use Case

Benny RochwergerResearch Staff Member

Haifa Research Lab.

OGSA-based Problem Determination: An Use Case2 © 2003 IBM Corporation

Agenda? The Open Grid Services Architecture

? Autonomic Computing

? The End to End Problem Determination Toolkit

? Lessons Learned

Haifa Research Lab.


Web Services in a Nutshell? A Web Service is an interface that describes a collection

of operations that are network accessible through standardized XML messaging

? A Web Service is described using a standard, formal

XML notion, called service description, which covers

message formats, transport protocols and location

? The interface hides the implementation details of the

service

Haifa Research Lab.


The Web Services Model? SOAP: Communication protocols

? WSDL: Service description

? UDDI: Service discovery

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What is missing in the Web Services Model ?

? Service description captures interface syntax

The service accepts an operation request with a particular signature

? Service description does not capture semantics

Operation should respond as expected

“As expected” is usually defined offline in specifications

Use names as basis for reasoning about semantics

Standardize common services and operations

Haifa Research Lab.


What is missing in the Web Services Model ? getQuote(“BMW”)

1. BMW K 1200 RS Mileage: 8266 Year: 1999 Price: £6950

2. BMW R 1100 S Mileage:10347Year: 1998 Price: £5750

3. BMW R 1100 S Mileage : 7284Year: 1999 Price: £6250

4. BMW R 1100 S Mileage: 9000Year: 2000 Price: £6350

Used Motorcycle dealer

BMW (ISE:BMW) Time: 7:11Last Price: 1961.00

Change: +18.00Open: 1942.00High: 1977.00 @ 5:41 ETLow: 1927.00 @ 3:16 ET

Currency: GBX

Stock Quotes Provider

Haifa Research Lab.


The Open Grid Services Architecture

? Extensions to existing Web Service technologies Transient stateful service instances

? Significant implications for how services are managed, named, discovered and used.

Standard interfaces and behaviors that address key distributed system issues

? Naming and bindings

? Information model

? Lifecycle

? Notification

Haifa Research Lab.


OGSA: Transient Service Instances

? “Web services” address discovery & invocation of persistent services Interface to persistent state of entire enterprise

? Must also support transient service instances, created/destroyed dynamically Interfaces to the states of distributed activities

E.g. workflow, video conf., dist. data analysis

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OGSA: Standard Interfaces & Behaviors? Naming and bindings

Every service instance has a unique name, from which can discover supported bindings

? Information model Service data associated with Grid service instances,

operations for accessing this info

? Lifecycle Service instances created by factories

Destroyed explicitly or via soft state

? Notification Interfaces for registering interest and delivering notifications

Haifa Research Lab.


Service Data

? A Grid service instance maintains a set of service data elements

XML fragments encapsulated in standard <name, type, TTL-info> containers

Includes basic introspection information, interface-specific data, and application data

? findServiceData operation (GridService interface) queries this information

Extensible query language support

? See also notification interfaces Allows notification of service existence and changes in service

data

Haifa Research Lab.


Lifetime Management

? GS instances created by factory or manually; destroyed explicitly or via soft state

Negotiation of initial lifetime with a factory (=service supporting Factory interface)

? GridService interface supports destroy operation for explicit destruction

setTerminationTime operation for keepalive

? Soft state lifetime management avoids Explicit client teardown of complex state

Resource “leaks”in hosting environments

Haifa Research Lab.


Factory

? Factory interface’s createService operation creates a new Grid service instance

Reliable creation (once-and-only-once)

? createService operation can be extended to accept service-specific creation parameters

? Returns a Grid Service Handle(GSH)

A globally unique URL

Uniquely identifies the instance for all time

Haifa Research Lab.


Notification Interfaces

? NotificationSource for client subscription One or more notification generators

Generates notification message of a specific typeTyped interest statements: E.g., Filters, topics, …Supports messaging services, 3rd party filter services, …

Soft state subscription to a generator

? NotificationSink for asynchronous delivery of notification messages

? A wide variety of uses are possible E.g. Dynamic discovery/registry services, monitoring,

application error notification, …

Haifa Research Lab.


The OGSA Framework

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? Lessons Learned

Haifa Research Lab.


Autonomic Computing AttributesAutonomic Computing AttributesSelfSelf--managing Systems that deliver...managing Systems that deliver...

Secure Information Secure Information and Resourcesand Resources

Anticipate, detect, Anticipate, detect, identify, and protect identify, and protect

against attacksagainst attacks

Increased Increased ResponsivenessResponsiveness

Adapt to dynamically Adapt to dynamically changing environmentschanging environments

Business Business ResiliencyResiliency

Discover, diagnose, Discover, diagnose, and act to preventand act to prevent

disruptionsdisruptions

Operational Operational EfficiencyEfficiency

Tune resources and Tune resources and balance workloads to balance workloads to maximize use of IT maximize use of IT resourcesresources

Haifa Research Lab.


A Holistic Approach to Autonomic ComputingA Holistic Approach to Autonomic Computing

??Service oriented Service oriented architecturearchitecture

??Virtualization of Virtualization of resourcesresources

??Automation & Automation & manageability manageability enablement for each enablement for each system elementsystem element

Web Services

System Mgmt Database

ISVSolutions

Servers Storage Network

Customer Applications

Application Servers

OGSAMeta OS Services

Architecture Framework

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Autonomic Computing Building BlocksAutonomic Computing Building Blocks

An autonomic elementcontains a continuous control loop that monitors activities and takes actions to adjust the system to meet business objectives

Autonomic elements learn from past experience to build action plans

Managed elements need to be instrumented consistently

Monitor Execute

Analyze Plan

Knowledge

Element

Sensors Effectors

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? Lessons Learned

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Hierarchical End-to-end Problem Determination

TheInternet

Tier 1Presentation Layer

Tier 2Application Layer

Tier 3Storage and Legacy

Tier 0Client Layer

Vertical PDHorizontal PD

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Managed Elements

The ePD Toolkit: Hierarchical, Heterogeneous Architecture

XX

ACAdapter

ACAdapter

DB2DB2

ACAdapter

ACAdapter

WASWAS

ACAdapter

ACAdapter

Event RepositoryEvent Repository

Autonomic ManagerRME/LogAnalyzer

Autonomic ManagerRME/LogAnalyzer

eMulsaeMulsa

ACAdapter

ACAdapter

Event RepositoryEvent Repository

Autonomic ManagerRAIL

Autonomic ManagerRAIL

Autonomic ManagerABLE

Autonomic ManagerABLE

EPPEPP

ACAdapter

ACAdapter

Orchestrator

OGSA InterfacesCBE payload

Data (CBE)

Control

PluggabilityComposabilityOrchestration

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The ePD Toolkit Guiding Concepts? Compose-ability

The ability to bind PD components into hierarchal end-to-end PD system

? Plug-ability The ability to switch components with similar functionality in a

complex PD system, e.g., Switch between LogAnalyzer and ABLE based analyser

? Orchestration The mechanism for automatic dynamic configuration and wiring of the

hierarchical PD system

The capability to instantiate and control, on demand, components/tools as a result of autonomous decisions of the PD system, e.g.,

Collects all messages coming from server that looks faulty

Haifa Research Lab.


The ePD Toolkit Highlights ? Hierarchical architecture

First level analysis identifies something wrong based on local information; it fires an event. Second level analysis can correlate this event with others events in the system (composability)

? Feedback mechanism Allows dynamic wiring and zooming in a particular problem

(orchestration) Demonstrate independent “Execute” component of MAPE

Plan decomposition, action distribution? Heterogeneous

Tools are combined to achieve a powerful system through standardinterfaces and common data representation

? Componentized Autonomic Manager “Standard” interfaces (plugability)

RME control, input and output thru Grid Services

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OGSA Based Problem Determination

« i n t e r f a c e »E f f e c t o r

+ s t a r t ( )+ s t o p ( )+ i n s t a l l ( )+ c o n f i g u r e ( )+ e x e c ( )

« i n t e r f a c e »S e n s o r

« i n t e r f a c e »N o t i f i c a t i o n S i n k

+ d e l i v e r N o t i f i c a t i o n ( )

« i n t e r f a c e »N o t i f i c a t i o n S o u r c e

+ s u b s c r i b e ( )+ u n s u b s c r i b e ( )

« i n t e r f a c e »G r i d S e r v i c e

+ f i n d S e r v i c e D a t a ( )+ s e t S e r v i c e D a t a ( )+ d e s t r o y ( )

« i n t e r f a c e »M a n a g e d R e s o u r c e

Haifa Research Lab.


Everything is a Managed Element

«interface»ManagedResource

ApacheManageResource

ACGenericAdapter ApacheProcess

«use»start/stop

«use»create/delete

«interface»AutonomicManager

RMEAutonomicManager

RMEProcess

«use»start/stop/create /delete

Haifa Research Lab.





? Lessons Learned

Haifa Research Lab.


OGSA Summary/Lessons Learned

§ The OGSA Programming Modelþ Reuse portTypes when possible

þ Extensibility types

ý Service data elements

þ Use of Factories

ý Explicit Lifecycle Management

§ The Notification Modelý Two entities: sink and source

ý Notifications on state changes only

Haifa Research Lab.

Nov. 24, 2003

OGSA-based Problem DeterminationAn Use Case

Benny RochwergerResearch Staff Member

ogsa-based problem determination an use case · the open grid services architecture? extensions to...

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