Motorola 6806800C47B manual Models and Concepts, Checkpoint Director, Checkpoint Node Director

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Introduction

Models and Concepts

 

 

1.2Models and Concepts

The Checkpoint service comprises three distributed subparts that maintain the cluster-wide checkpoint database.

zCheckpoint Director

zCheckpoint Node Director

zCheckpoint Agent

Figure 1-1 Checkpoint Service -Subparts

CPD

CPD

Payload Blade 1

Payload Blade 2

active

standby

 

 

CPND

CPND

CPN D

C PND

C PA

C PA

CPA

C PA

A pplication

A pplication

A pplication

A pplication

Node SMH 1

Node SMH 2

 

 

CPD - Checkpoint Director

 

Communication path (MDS)

CPND - Checkpoint Node Director

 

Communication path (MBCSv)

CPA - Checkpoint Agent

 

 

 

SMH - System Manager Host

 

 

1.2.1Checkpoint Director

Checkpoint Director (CPD) runs as a process on a system manager node. CPD maintains the centralized repository of control information for all checkpoints created in the cluster. The CPD also maintains the location information of active replicas for all the checkpoints opened in the cluster. In case of non-collocated checkpoint, the CPD designates a particular node to manage an active replica for that checkpoint and also decides on the number or replicas to be created which depends on the policy (See section 8.1.5.1 Usage of Non-Collocated Checkpoints, for policies). Two instances of CPD are configured, one on each system manager node, in order to achieve high-availability. The two instances are configured to be part of a service group having a 2N redundancy model.

1.2.2Checkpoint Node Director

There is one instance of the Checkpoint Node Director (CPND) on each system manager and payload nodes. It is modeled as a separate process. CPND maintains the detailed information of the Checkpoints referred from that node and the corresponding updates and retrievals that operate on those checkpoints. CPND also handles the requests issued by the CPA instances on behalf of its client applications on the same node. In case of checkpoints that have been created with the collocated attribute and the asynchronous update option, the application will

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Checkpoint Service Programmer’s Reference (6806800C47B)

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Contents Checkpoint Service Trademarks Contents Contents List of Tables List of Tables Checkpoint Service -Subparts List of FiguresList of Figures Abbreviations Overview of ContentsAbout this Manual Notation Description ConventionsAbout this Manual Abbreviation Definition Bold About this Manual Summary of Changes Comments and Suggestions Part Number Publication Date DescriptionAbout this Manual Introduction OverviewCheckpoint Node Director Models and ConceptsCheckpoint Director Introduction Models and ConceptsCheckpoint Agent Compliance Table Checkpoint ServiceCompliance Report Checkpoint Agent IntroductionRelated SAF Standard Documents Introduction Related SAF Standard DocumentsNcsCkptRegisterCkptArrivalCallback Service ExtensionsAPI Description NcsCkptRegisterCkptArrivalCallback ParametersNcsCkptCkptArrivalCallback Parameters 2 *ncsCkptCkptArrivalCallbackNcsCkptRegisterCkptArrivalCallback Return Values API Description NcsCkptCkptArrivalCallbackImplementation Notes API Description Implementation NotesUsage of Non-Collocated Checkpoints Cancellation of Pending Callbacks ConfigurationTime-out Arguments for Checkpoint Service APIs Maximum Number of Replicas Per NodeShared Memory Configuration API Description Service DependenciesShared Memory Configuration Maximum Data Size Per One write or OverwriteMIB table id \ trap id Description Management InterfaceSAF-CHK-SVC-v75 MIB Run the Checkpoint Service Demo Sample ApplicationSample Application Output Sample Application Sample Application OutputTable B-1 Motorola Publications Related DocumentationMotorola Embedded Communications Computing Documents Document Title Publication NumberRelated Documentation Related Specifications Related SpecificationsTable B-2 Related Specifications Document Title Version/Source
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