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Veritas Storage Foundation

and High AvailabilitySolutions ReplicationAdministrator's Guide

Linux

6.0

November 2011


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Veritas Storage Foundation and High AvailabilitySolutions Replication Administrators Guide

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Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . .4

Chapter 1 Introducing Veritas Replicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . .21

About Veritas Replicator.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .21

What is VFR... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . .21

Features of VFR... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .22

What is VVR?... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .22Features of VVR... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

Section 1 Getting started with Veritas File

Replicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .25

Chapter 2 Introducing Veritas File Replicator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27

About Veritas File Replicator.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . .27

How Veritas File Replicator works.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .28

System requirements.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Veritas File Replicator limitations.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .29

Chapter 3 Administering Veritas File Replicator. . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

About Veritas File Replicator administration... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .31

Starting the vxfstaskd and vxfsrepld daemons... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32

Creating a replication job.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .34

Managing a replication job.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .35

Displaying replication job information... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . .36

Displaying replication jobs.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .36

Displaying the status of a replication job.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Displaying replication job statistics.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .38

Displaying a replication Storage Checkpoint.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39

Modifying a replication job.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . .39

Deleting a replication job.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . .42

About Veritas File Replicator log files.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . .42

About error recovery after a site disaster or network disruption... . . . . . . . .43

Performing a manual failover.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .43

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Recovering data after a disaster.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .44

Changing the replication direction... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . .46

Section 2 Getting started with Veritas VolumeReplicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .49

Chapter 4 Introducing Veritas Volume Replicator. . . . . . . . . . . . . . . . . . . . . . . . . .51

How VVR processes application writes.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .52

Components of VVR... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53

Replicated Volume Group (RVG).. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .54

Storage Replicator Log (SRL).. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .55

Replication Link (RLINK).. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . .55

Data Change Map (DCM).. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .56Replicated Data Set (RDS).. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .56

Replication terms defined.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .57

Write-order fidelity.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57

Consistent data versus current or up-to-date data.. . . . . . . . . . . . . . . . . . . . . . . . . . . . .58

IPv4-only node.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . 58

IPv6-only node.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . 58

Dual-node / Dual-stack.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .58

IPv6-enabled node.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59

How the VVR components fit together.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . .59

VVR at the Primary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59

VVR at the Secondary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59

Local host (localhost). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60

About modes of replication... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .60

Introducing the VCS agents for VVR... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .61

Chapter 5 Understanding how Veritas Volume Replicatorworks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .63

About Veritas Volume Replicator concepts.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .64

How data flows in VVR asynchronous mode... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .64

About secondary logging enabled asynchronous mode... . . . . . . . . . . . . . . . . . . . . .65How data flows in VVR asynchronous mode with secondary

logging.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .66

How data flows in VVR synchronous mode... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .67

How data flows in an RDS containing multiple Secondary hosts.. . . . . . . . . . .68

Replication in a shared disk group environment.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70

The role of the logowner.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .71

How VVR processes a write in a shared disk group... . . . . . . . . . . . . . . . . . . . .72

How VVR processes a read in a shared disk group... . . . . . . . . . . . . . . . . . . . . .75

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Understanding how VVR logs writes to the SRL... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76

Understanding Storage Checkpoints.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .78

Volume sets in VVR... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80

Changing membership of an RVG and a volume set.. . . . . . . . . . . . . . . . . . . . . . . . . . .80Using SmartTier with VVR... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . .82

Best practices.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82

Cross-platform Data Sharing in VVR... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . .82

Understanding the VVR snapshot feature .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .83

Snapshots of RVGs containing volume sets.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84

About the traditional snapshot feature.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . .85

About the instant snapshot feature.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . .85

How VVR creates instant space-optimized snapshots.. . . . . . . . . . . . . . . . . . .87

Comparing the snapshot methods based on different

features.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89

About VVR compression... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90General functionality considerations for VVR compression... . . . . . . . .91

Chapter 6 Planning and configuring replication. . . . . . . . . . . . . . . . . . . . . . . . . . . . .93

Introduction to planning and configuring replication... . . . . . . . . . . . . . . . . . . . . . .93

Data flow in VVR... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94

About replication in synchronous mode... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95

Data flow when reading back from the SRL... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96

Before you begin configuring.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .96

Understanding business needs.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . .97

Understanding application characteristics.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97

Choosing the mode of replication... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .98

Asynchronous mode considerations.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . .98

Synchronous mode considerations.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . .99

Asynchronous replication versus synchronous replication... . . . . . . . .102

Choosing latency and SRL protection... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . .103

Planning the network.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104

Choosing the network bandwidth.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .105

Choosing the network protocol.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . .106

Choosing the network ports used by VVR... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107

Configuring VVR in a firewall environment.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108Choosing the packet size.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .109

Choosing the network maximum transmission unit.. . . . . . . . . . . . . . . . . . .110

Sizing the SRL... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110

Peak usage constraint.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . .111

Synchronization period constraint.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .113

Secondary backup constraint.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .114

Secondary downtime constraint.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . .115

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Additional factors.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116

Example.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117

How the agents for hybrid applications work.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118

Overview of how to configure VVR in a VCS environment.. . . . . . . . . . . . . . . . .119Overview of how to configure the primary-elect feature in a VCS

globally clustered environment.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . .119

Generic VVR setup in a VCS environment.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .120

Example VVR configuration in a VCS environment.. . . . . . . . . . . . . . . . . . . . . . . . . .121

Chapter 7 Understanding replication settings for aSecondary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123

About replication settings for a Secondary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123

Modes of replication... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124

Asynchronous replication... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .124Synchronous replication... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .125

The synchronous attribute.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . .125

Protecting against SRL overflow... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .126

The srlprot attribute.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . .127

Setting up latency protection... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .129

The latencyprot attribute.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .130

Controlling the network bandwidth used for replication... . . . . . . . . . . . . . . . . .131

Choosing the compression mode... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .132

Enabling compression... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .133

Disabling compression... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .134

Chapter 8 Configuring the agents for high availability. . . . . . . . . . . . . . . .137

Requirements for configuring VVR in a VCS environment.. . . . . . . . . . . . . . . . .137

Best practices for setting up the agents.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .138

Example configuration for a failover application... . . . . . . . . . . . . . . . . . . . . . . . . . . .139

Example configuration for a parallel application... . . . . . . . . . . . . . . . . . . . . . . . . . . .140

Examplesetting up VVR in a VCS environment.. . . . . . . . . . . . . . . . . . . . . . . . . . . . .142

Setting up the VVR configuration... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . .143

Verifying the VVR replication state.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . .146

Configuring the agents for failover applications.. . . . . . . . . . . . . . . . . . . . . . . .146

Configuring the agents for parallel applications.. . . . . . . . . . . . . . . . . . . . . . . .153

Configuring the agents for a bunker replication configuration... . . . . . . . . .156

VCS configuration for a bunker using the STORAGE

protocol.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .156

VCS configuration for a bunker using IP.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .158

How the RVGPrimary works in a bunker setup... . . . . . . . . . . . . . . . . . . . . . . . .158

About choosing the Primary site after a site disaster or network

disruption... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160

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Application availability in the case of a network disruption... . . . . . . .161

Configuring VCSglobal clustering so you can choose thePrimary

site.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . 163

Choosing the Primary site after a site disaster or networkdisruption... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163

Troubleshooting the primary-elect feature.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165

Administering the service groups.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .167

Section 3 Analyzing your environment with Volume

Replicator Advisor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . .169

Chapter 9 Introducing Veritas Volume Replicator Advisor

(VRAdvisor) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .171

Audience.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . 171

Related Veritas documents.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . .172

Overview of VRAdvisor.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . .172

How VRAdvisor works.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .173

Data collection... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173

Data analysis.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174

What-if analysis.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174

Chapter 10 Collecting the sample of data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . .175

About collecting the sample of data.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . .175Best practices for collecting the sample of data.. . . . . . . . . . . . . . . . . . . . . . . . .175

Collecting the sample of data on UNIX... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . .176

Prerequisite for collecting the sample of data.. . . . . . . . . . . . . . . . . . . . . . . . . . .176

Supported locales.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . .176

Collecting data using the VRAdvisor wizard.. . . . . . . . . . . . . . . . . . . . . . . . . . . . .177

Collecting data using the vxstat command... . . . . . . . . . . . . . . . . . . . . . . . . . . . . .180

Collecting data using the data collection script.. . . . . . . . . . . . . . . . . . . . . . . . .180

Examples of collecting data with the data collection script.. . . . . . . . . .183

Collecting the sample of data on Windows... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .184

Prerequisite for collecting the sample of data.. . . . . . . . . . . . . . . . . . . . . . . . . . .184Collecting the sample of data using the VRAdvisor wizard.. . . . . . . . . .184

Collecting the sample of data using the diskStats command... . . . . . .185

Chapter 11 Analyzing the sample of data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .187

About analyzing the sample of data.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .187

Prerequisites for analyzing the sample of data.. . . . . . . . . . . . . . . . . . . . . . . . . .188

Launching the VRAdvisor wizard.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .188

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Analyzing the collected data.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . .188

Specifying the data for analysis.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .189

Specifying the parameters for analysis.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192

Understanding the results of the analysis.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . .193Viewing the analysis results.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .193

Recalculating the analysis results.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . .195

Recording and viewing the results.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .200

Chapter 12 Installing Volume Replicator Advisor(VRAdvisor) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201

System requirements.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .201

Installing VRAdvisor on Solaris.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .202

Uninstalling VRAdvisor on Solaris.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .202

Installing VRAdvisor on Windows... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .202Uninstalling VRAdvisor on Windows... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .203

Section 4 Setting up and administering VVR . . . . . . . . . . . . . . . . . .205

Chapter 13 Setting up replication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .207

About configuring replication... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .207

Best practices for setting up replication... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .208

Creating a Replicated Data Set.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .210

Creating a Primary RVG of an RDS... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .210

Adding a Secondary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . .213

Changing the replication settings for a Secondary.. . . . . . . . . . . . . . . . . . . . .218

Synchronizing the Secondary and starting replication... . . . . . . . . . . . . . . . . . . .226

Methods to synchronize the Secondary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .226

Using the automatic synchronization feature.. . . . . . . . . . . . . . . . . . . . . . . . . . .228

Example for setting up replication using automatic

synchronization... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .230

About SmartMove for VVR... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .231

About thin storage reclamation and VVR... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231

Determining if a thin reclamation array needs reclamation... . . . . . . .232

Starting replication when the data volumes are zero initialized.. . . . . . . . .233Example: Starting replication when the data volumes are zero

initialized.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .233

Chapter 14 Displaying configuration information. . . . . . . . . . . . . . . . . . . . . . . . . . .235

Displaying RVG and RDS information... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . .235

Displaying RDS information... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .236

Displaying an individual RVG... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .236

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Interpreting RVG flag settings.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . .237

Displaying information about data volumes and volume sets.. . . . . . . . . . . . .237

Displaying data volumes in a Replicated Data Set.. . . . . . . . . . . . . . . . . . . . . .237

Displaying a list of data volumes.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . .238Displaying information about all failed data volumes.. . . . . . . . . . . . . . . . .238

Displaying an individual data volume... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .238

Displaying a volume set.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .238

Displaying information about Secondaries.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . .239

Displaying consolidated replication status.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .239

Displaying a list of RLINKs... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .246

Displaying a specific RLINK... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .246

Displaying the status of a Secondary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .249

Displaying a list of Storage Checkpoints.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . .251

Displaying statistics with the vrstat display commands.. . . . . . . . . . . . . . . . . . . .253

Displaying the consolidated statistics.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .253Displaying the RLINK information for all the hosts in the

RDS... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253

Displaying information about all the data volumes for all the

hosts in the RDS... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . .254

Displaying information about the SRL volumes for all the hosts

in the RDS... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256

Displaying information about the memory tunable parameters

for all the hosts in the RDS... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . .257

Determining VVR network bandwidth usage and compression

ratio.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .258Collecting consolidated statistics of the VVR components.. . . . . . . . . . . . . . . . .259

Understanding how VVR stores the statistics.. . . . . . . . . . . . . . . . . . . . . . . . . . .261

Displaying network performance data.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . .262

Displaying extended replication statistics.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .263

Identifying the most up-to-date Secondary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .265

VVR event notification... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .268

Chapter 15 Administering Veritas Volume Replicator. . . . . . . . . . . . . . . . . . . .271

Administering data volumes.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . .271

Associating a volume to a Replicated Data Set.. . . . . . . . . . . . . . . . . . . . . . . . . . .272Associating a volume set to an RDS... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . .277

Associating a Data Change Map to a data volume... . . . . . . . . . . . . . . . . . . . . .281

Resizing a data volume in a Replicated Data Set.. . . . . . . . . . . . . . . . . . . . . . . .284

Dissociating a data volume from its Replicated Data Set.. . . . . . . . . . . . .286

Administering the SRL... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .289

Protecting from SRL overflow... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . .290

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Incrementally synchronizing the Secondary after SRL

overflow... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .290

Changing the size of the SRL on the Primary and the

Secondary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .295Administering replication... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .297

Changing the replication settings.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . .297

Pausing and resuming replication to a Secondary.. . . . . . . . . . . . . . . . . . . . . .297

Stopping replication to a Secondary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .298

Changing the IP addresses used for replication... . . . . . . . . . . . . . . . . . . . . . . .299

Changing the network ports used for replication... . . . . . . . . . . . . . . . . . . . . .306

Administering the Replicated Data Set.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . .310

Removing a Secondary from a Replicated Data Set.. . . . . . . . . . . . . . . . . . . . .311

Removing a Primary RVG... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . .312

Administering Storage Checkpoints.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . .313

Creating Storage Checkpoints.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . .313Ending Storage Checkpoints.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .313

Viewing Storage Checkpoints.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . .314

Deleting Storage Checkpoints.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . .314

Creating RVG snapshots.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .315

Using the instant snapshot feature.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . .315

Instant full snapshot.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .316

Instant space-optimized snapshots.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .321

Instant plex-breakoff snapshots.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . .326

Administering snapshots.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .328

Using the traditional snapshot feature.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .334Using Veritas Volume Manager FastResync.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .339

Verifying the DR readiness of a VVR setup... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .340

Performing a failover.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .341

Performing a fire drill. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .341

Verifying the data on the Secondary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..342

Backing up the Secondary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .348

Storage Checkpoint pause/resume Secondary RLINK ... . . . . . . . . . . . . . . .348

Restoring the Secondary from online backup... . . . . . . . . . . . . . . . . . . . . . . . . . .349

Chapter 16 Using VVR for off-host processing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .353

About using VVR for off-host processing.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .353

What is off-host processing?.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .354

In-Band Control Messaging overview... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . .354

How to use the data on the Secondary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .354

In-BandControl Messaging explained... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . .355

Performing off-host processing tasks.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . .359

Tasks to perform for off-host processing.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .359

Contents14


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Using the IBC messaging command vradmin ibc.. . . . . . . . . . . . . . . . . . . . . . . .360

Examples of off-host processing.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .365

Example 1Decision support using thesnapshotfeature andthe

vradmin ibc command... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .365Example 2Backing up using the snapshot feature and the

vradmin ibc command... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .367

Example3Performingblock-level backupof theSecondarydata

using the vradmin ibc command... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .368

Chapter 17 Transferring the Primary role . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .371

About transferring the Primary role.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .371

Migrating the Primary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . .372

Prerequisites for migrating the Primary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .374

Important notes for migrating the Primary role.. . . . . . . . . . . . . . . . . . . . . . . .375Example 1Migrating from a healthy Primary.. . . . . . . . . . . . . . . . . . . . . . . . . .376

Example 2Migrating the Primary role in a setup with multiple

Secondaries.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .377

Taking over from an original Primary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .380

Important notes about taking over from an original

Primary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .382

Example 1Taking over from an original Primary.. . . . . . . . . . . . . . . . . . . . .385

Example2Takingover from an original Primary in a setup with

multiple Secondaries.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .386

Failing back to the original Primary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . .388

Fast failback versus difference-based synchronization... . . . . . . . . . . . . .389

Failing back using fast failback synchronization... . . . . . . . . . . . . . . . . . . . . .389

Failing back using difference-based synchronization... . . . . . . . . . . . . . . .395

About choosing the Primary site after a site disaster or network

disruption... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .398

Application availability in the case of a network disruption... . . . . . . . . . . . . .399

Configuring VCS global clustering so you can choose the Primary

site.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . 401

Choosing the Primary site after a site disaster or network

disruption... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .402

Example 1

Choosing the original Primary as the Primary goingforward... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .402

Example 2 Choosing the original Secondary as the Primary

going forward... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .403

Troubleshooting the primary-elect feature.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..404

Troubleshooting failures in the RVGPrimary online agent

function... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .404

Troubleshooting failures in VVR ElectPrimary command... . . . . . . . . . .405

Contents


16/584

Limitations.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . 406

Chapter 18 Replicating to a bunker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .407

Introduction to bunker replication... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .407

Bunker replication during normal operations.. . . . . . . . . . . . . . . . . . . . . . . . . . .408

How the bunker is used for disaster recovery.. . . . . . . . . . . . . . . . . . . . . . . . . . . .409

Best practices for setting up bunker replication... . . . . . . . . . . . . . . . . . . . . . .411

Sample configuration... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .411

Setting up bunker replication ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .412

Requirements for bunker replication... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .412

Best practices for setting up bunker replication... . . . . . . . . . . . . . . . . . . . . . .413

Adding a bunker to an RDS... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .413

Changing replication settings for the bunker Secondary.. . . . . . . . . . . . .416

Starting replication to the bunker.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . .418Reinitializing the bunker.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . .418

Administering bunker replication... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .419

Using a bunker for disaster recovery .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .419

Updating the Secondary from the bunker.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .419

Restoring the original Primary in a bunker setup... . . . . . . . . . . . . . . . . . . . .421

Bunker replication in a VCS environment.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . .424

Automating local cluster failover for a bunker.. . . . . . . . . . . . . . . . . . . . . . . . . .424

Bunker replay in a VCS environment.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .426

Removing a bunker .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .427

Bunker commands.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .427

Chapter 19 Troubleshooting VVR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . .429

Recovery from RLINK connect problems... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .429

Recovery from configuration errors.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .432

Errors during an RLINK attach... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . .432

Errors during modification of an RVG... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .435

Recovery.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . .440

Primary-host crash... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .440

Recovering from Primary data volume error.. . . . . . . . . . . . . . . . . . . . . . . . . . . . .440

Primary SRL volume error cleanup and restart.. . . . . . . . . . . . . . . . . . . . . . . . .443

Primary SRL volume error at reboot.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .444

Primary SRL volume overflow recovery.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .445

Primary SRL header error cleanup and recovery.. . . . . . . . . . . . . . . . . . . . . . .445

Secondary data volume error cleanup and recovery.. . . . . . . . . . . . . . . . . . .446

Secondary SRL volume error cleanup and recovery.. . . . . . . . . . . . . . . . . . . .448

Secondary SRL header error cleanup and recovery.. . . . . . . . . . . . . . . . . . . .448

Secondary SRL header error at reboot.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .451

Contents16


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Appendix A VVR command reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .453

VVR command reference.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .453

Appendix B Using the In-band Control Messaging utility vxibcand the IBC programming API . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .465

About the IBC messaging utility vxibc.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .465

In-band Control Messaging overview... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .466

Using the IBC messaging command-line utility.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .467

Registering an application name... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .467

Displaying the registered application name for an RVG... . . . . . . . . . . . .467

Receiving an IBC message.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .468

Sending an IBC message.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .468

Unfreezing the Secondary RVG... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . .469Unregistering an application name... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .469

Receiving and processing an IBC message using a single

command... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .470

Sending and processing an IBC message using a single

command... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .470

ExamplesOff-host processing.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .471

Example 1Decision support using the traditional snapshot

feature and the vxibc utility.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . .472

Example 2Backing up using the snapshot feature andthe vxibc

utility.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .473

Example 3Trial failover using the snapshot feature.. . . . . . . . . . . . . . . . .474Example 4Decision support using the instant full snapshot

feature and the vxibc utility.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . .475

In-band Control Messaging API.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .476

IOCTL commands.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .477

Using the IBC API.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .483

Appendix C Veritas Volume Replicator object states. . . . . . . . . . . . . . . . . . . . . . .485

Veritas Volume Replicator Kernel State.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . .485

RVG KSTATEs... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .485

RLINK KSTATEs... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .486Veritas Volume Replicator utility states.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . .486

RVG utility states.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .486

RLINK utility states.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .486

Inactive RLINKs... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . .487

STALE RLINK state.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .487

FAIL RLINK state.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .488

Inconsistent RLINKs... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .489

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Pausing, resuming, and restoring RLINK states.. . . . . . . . . . . . . . . . . . . . . . . . .490

Appendix D VVR task reference. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .491

Mappingthename of a Secondarydata volume to a differently named

Primary data volume... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . .491

Mapping disk groups.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .493

Decreasing the size of the SRL on the Primary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .494

Appendix E Alternate methods for synchronizing theSecondary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .497

Using the full synchronization feature.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .497

ExampleSynchronizing the Secondary using full

synchronization with Storage Checkpoint.. . . . . . . . . . . . . . . . . . . . . . . . . .499

Using block-level backup and Storage Checkpoint.. . . . . . . . . . . . . . . . . . . . . . . . . . .500

ExampleSynchronizing the Secondary using block-level

backup... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .501

Using the Disk Group Split and Join feature.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..502

Using difference-based synchronization... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . .504

Examplesynchronizing the Secondary based on

differences.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .506

Examples for setting up a simple Volume Replicator

configuration... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .507

Creating a Replicated Data Set for the examples.. . . . . . . . . . . . . . . . . . . . . . . .508

Example for setting up replication using fullsynchronization... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .509

Example for setting up replication using block-level backup and

checkpointing.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .510

Example for setting up replication using Disk Group Split and

Join.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .511

Example for setting up replication using differences-based

synchronization... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .514

Example for setting up replication when data volumes are

initialized with zeroes.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . .514

Appendix F Migrating VVR from Internet Protocol version 4 toInternet Protocol version 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .517

Overview of VVR migration... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .517

Migrating to IPv6 when VCS global clustering and VVR agents are

not configured.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .518

Understanding the current configuration... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .518

Migration prerequisites.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . .521

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Migrating from IPv4 to IPv6... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .521


configured.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .530

Understanding the current configuration... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .530Migration prerequisites.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . .532

Migrating to IPv6... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .533

Migrating the VCS global clustering service group to IPv6... . . . . . . . . .533

Adding IP andNIC resources for IPv6 addresses in theRVGagent

group... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .536

Migrating VVR RLINKs from IPv4 to IPv6... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .538

Removing the IPv4 resources from the VCS configuration... . . . . . . . . .539


configured in the presence of a bunker.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .539

Understanding the current configuration... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .539

Migration prerequisites.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . .543Migrating to IPv6... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .543

Appendix G Sample main.cf files. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . .565

Globally clustered VCS and VVR main.cf. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .565

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .571

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Introducing VeritasReplicator

This chapter includes the following topics:

About Veritas Replicator

What is VFR

Features of VFR

What is VVR?

Features of VVR

About Veritas ReplicatorVeritas Replicator from Symantec provides organizations with a comprehensive

solution for heterogeneous data replication. As an option to Veritas Storage

Foundation,Veritas Replicator enables cost-efffective replication of data over IP

networks, giving organizations an extremely flexible, storage hardware

independent alternative to traditional array-based replication architectures.

Veritas Replicator provides the flexibility of block-based continuous replication

with Veritas Volume Replicator (VVR) and file-based periodic replication with

Veritas File Replicator (VFR).

What is VFRVeritas File Replicator (VFR) enables cost-effective periodic replication of data

over IP networks, giving organizations an extremely flexibilestorage independent

data availability solution for disaster recovery and off-host processing. With

flexibility of scheduling the replication intervals to match the business

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requirements, Veritas File Replicator tracks all updates to the File System and

replicates these updates at the end of the configured time interval. VFR leverages

data deduplication provided by Veritas File System (VxFS) to reduce the impact

that replication can have on scarce network resources. VFR is included, by default,with Symantec Virtual Store 6.0on Linux andis available as an option with Veritas

Storage Foundation and associated products on Linux.

Features of VFRVeritas File Replicator (VFR) includes the following features:

Supports file system level replication of application data.

Supports reversible data transfer. The target of replication may become the

source at runtime, with the former source system becoming a target. Provides efficiency of data transfer when transferring shared extents, so that

the data is not sent multiple times over the network.

Supports automatic recovery from the last good successfully replicated point

in time image.

Periodically replicates changes. The interval is configurable by the user.

Supports deduplication to increase storage efficiency on the target system.

What is VVR?Veritas Volume Replicator (VVR) is data-replication software designed to

contribute to an effective disaster recovery plan. VVR enables you to maintain a

consistent copy of application data at one or more remote locations.

VVR is an option of Veritas Volume Manager (VxVM) that works as a fully

integrated component of VxVM. VVR benefits from the robustness, ease of use,

and high performance of VxVM, and at the same time, adds replication capability

to VxVM. VVR can replicate existing VxVM configurations, and can be

transparently configured while the application is active.

VVR is a separately licensed option of VxVM. You can start using VVR in a VxVMconfiguration by installing a valid VVR license.

VVR replicates the application writes on the volumes at the source location to

one or more remote locations across any distance. It provides a consistent copy

of application data at the remote locations. If a disaster occurs at the source

location, you can use the copy of the application data at the remote location and

restart the application at the remote location.

Introducing Veritas ReplicatorFeatures of VFR

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The host at the source location on which the application is running is known as

the Primary host, and the host at the target location is known as the Secondary

host. You can have up to 32 Secondary hosts in a VVR environment.

Thevolumes on thePrimary host must be initially synchronized with thevolumeson theSecondaryhost. VVRprovides several methods to initialize theapplication

data between the primary location and the remote location, such as using the

network, using tape backup, and moving disks physically.

Features of VVRVeritas Volume Replicator (VVR) includes the following features:

Can be configured to work with any storage hardware supported by Veritas

Volume Manager. Replicates data for up to 32 remote locations over any IP network in a LAN or

WAN environment.

Performs replication ofvolumegroupsin asynchronousor synchronous modes,

ensuring data integrity and consistency in both modes.

Maintains write-order fidelity, which applies writes on the Secondary host in

the same order that they were issued on the Primary host.

Enables you to easily recover your application at the remote site.

Provides effective bandwidth management using bandwidth throttling and

multiple connections.

Provides the ability to perform off-host processing such as Decision Support

Systems (DSS) and backup, by enabling you to break off a consistent mirror

or snapshot of the data volumes on the Secondary to use for these operations.

Provides the command-line interface and the graphical user interface for

online management of the VVR environment.

Provides multiple methods to synchronize the data at the Secondary location

with the data at the Primary location.

Easily accommodates growth of application data and system configurations.

Supports cross-platform replication, that is, the Primary and Secondary can

have different operating systems.

Supports volume-level replication of application or file system data, which

includes support for all commercial database management systems, such as

Oracle, DB2, Sybase, and Informix.

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Supports volume-level replication of data in a shared storage environment,

forusewith parallelapplications,such as OracleRAC(Real ApplicationCluster).

Supports replication of VxVM volume sets, including ensuring consistency

between the component volumes of the volume set on the Primary and on theSecondary.

Supports replication in a PDC (Portable Data Container) environment.

Supports different volume layouts on Primary and Secondary hosts. For

example mirrored layout is supported on Primary hosts and non-mirrored

layout is supported on Secondary hosts.

Provides the ability to validate data on the Secondary without application

downtime or stopping replication.

Providesa configurationcheck utility, /etc/vx/diag.d/vvrcheck, that displays

current replication status, detects and reports configuration anomalies, and

creates statistics files that can be used by display tools.

For more information, see the vvrcheck(1M) man page.

Introducing Veritas ReplicatorFeatures of VVR

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Getting started with Veritas

File Replicator

Chapter 2. Introducing Veritas File Replicator

Chapter 3. Administering Veritas File Replicator

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Introducing Veritas FileReplicator


About Veritas File Replicator

How Veritas File Replicator works

System requirements

Veritas File Replicator limitations

About Veritas File ReplicatorVeritas File Replicator (VFR) is data-replication software designed to contribute

to an effective disaster recovery plan. VFR enables you to maintain a consistent

copy of application data at a remote location.

VFR replicates the application writes on the file system at the source location a

remote location across any distance. If a disaster occurs at the source location,

you can use the copy of the application data at the remote location and restart

the application at the remote location. Aside from disaster recovery, VFR can be

used for content distribution, off host processing, and data migration.

The host at the source location on which the application is running is known asthe Primary host, and the host at the target location is known as the Secondary

host.

In thisrelease VFR is only supported on SUSE Linux Enterprise Server(SLES) and

Red Hat Enterprise Server (RHEL) Linux for Veritas Storage Foundation, Veritas

Storage Foundation and High Availability, Veritas Storage Foundation Cluster

File System High Availability (SFCFS) and Symantec VirtualStore.

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How Veritas File Replicator worksVeritas File Replicator provides replication where the replication unit is a file

system. VFR replicates an entire file system to a single target. The replicated filesare sentover the network ona periodic basis with a periodranging from15minutes

to a 180 minutes. The target is updated to match the current status of the source

files as of the most recent start of replication using Storage Checkpoints. The

changes since thelast replication iterationareefficiently identified using theFCL

(File ChangeLog) andStorageCheckpoints. To performfilebased replication using

VFR, you must specify a replication job and a replication group.

A replication job is directional. The job definition includes the source and

destination, both host addresses, andthemount points. It also includes theinterval

at whichincremental replication is scheduled. At each interval,a file systempoint

in time image is taken and the file/directory changes are sent to the target as astream of deltas where it is applied to have the target image mirror the point in

time image of the source.

A replication group is a set of files and directories in one or more file systems that

have to be replicated as an atomic entity from a point in time image. The point in

time image of all of those entities corresponds to the same point in time image,

irrespective of whether they are in the same file system or several file systems.

A replication job is successful only if all the files and directories in the replication

group are successfully replicated.

In this release of VFR, the scope of replication is limited to the replication group

being an entire file system.

At system startup, if enabled, the replication scheduler and the replication

daemons are started. Once the replication job is started using thevfradmin

command, the scheduler daemon takes a file system Storage Checkpoint, enables

the FCL if it is not already enabled and starts the replication process against the

newly created Storage Checkpoint. Old Storage Checkpoints are removed once

they are no longer useful.

The replication daemon is useful on machines that act as a replication target. It

listens for incomingconnections and appliesthechanges on thetarget file system.

After every iteration, a file system Storage Checkpoint is taken. The old Storage

Checkpoint is deleted once a new one is created.

The Storage Checkpoints used by VFR are data full checkpoints and will consume

extra storage on both the source and the target file systems. Also note that the

FCL is enabled by VFR and it is not advisable that you disable some FCL events or

disable the FCL entirely. VFR will detect such events and will use a less efficient

method to identify the changed files and directories. VFR will also enable the

missing FCL events and turn FCL back on.

Introducing Veritas File ReplicatorHow Veritas File Replicator works

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System requirementsVeritas File Replicator is available only on systems meeting the following

requirements: Systems running SLES or RHEL

The minimum file system layout Version is 9 on the source and target

Veritas File Replicator limitationsVeritas File Replicator has the following limitations:

Replication of compressed files on the source system does not result in

compressed files on the target system.

VFR is only supported on source and target systems with Veritas File System

(VxFS) file systems with disk layout version 9.

File systems are identified only by mount point and file system type. If a

different file system is mounted in place of the original file system used, VFR

may not detect the new file system.

VFR replicates in one direction, however the replication direction can be

manually changed in the event of a disaster.

VFR does not provide any security options and must run on a private secure

network if security is desired.

The source and destination file systems must have the same file system block

size.

VFR daemons are not highly available.

Cluster mounts used on a target must be managed by VCS.

If replication is enabled for a file system, it should not be resized to a smaller

size usingfsvoladm resizecommand.

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Introducing Veritas File ReplicatorVeritas File Replicator limitations

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Administering Veritas FileReplicator


About Veritas File Replicator administration

Starting the vxfstaskd and vxfsrepld daemons

Creating a replication job

Managing a replication job

Displaying replication job information

Modifying a replication job

Deleting a replication job

About Veritas File Replicator log files

About error recovery after a site disaster or network disruption

About Veritas File Replicator administrationVeritas File Replicator (VFR) lets you configure and control a system to

automatically replicate the data in a source file system to a matching file system

on anysystem over thenetwork.This replication is performed incrementally after

the initial synchronization by transferringthe deltas between successive versions

of the data. Thevfradminutility lets you manage and control the file replication

feature. The utility lets you view and modify the configuration of a replication

job as well as start or stop the replication job.

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Theconfiguration and thestatus files for an individual file system aresaved under

the lost+found directory on that file system. This allows the replication system

to access the data when storage devices are moved between nodes in a clustered

environment.

Note:Deleting thelost+founddirectory on the file system also deletes the

configuration and status files for the replication job, and you will not be able to

start the replication for the file system. The scheduler will drop the task for

running the replication job.

Beforestarting a replication job, youmust run the scheduler daemon(vxfstaskd)

and the replication target daemon (vxfsrepld).

Starting the vxfstaskd and vxfsrepld daemonsThevxfstaskddaemon is a scheduler daemon that takes scheduled Storage

Checkpoints, starts the replication process against newly created Storage

Checkpoints, andcleans up unused StorageCheckpoints. The daemon periodically

scans Veritas File System (VxFS) mount points for replication job configuration

and automatically schedules any enabled jobs. The vxfstaskddaemon must be

started on the source system before a replication job can be scheduled.

Thereplication schedulerandtargetdaemoncanbe started andstopped by either

using the init script located at /etc/init.d/vxfs_replicationor by runningthevfradmincommand directly. To start both the daemons using the init script,

run following command on both the source and the target system:

# /etc/init.d/vxfs_replication start

By default, the init script will not start the daemons at system bootup or when

run manually. If you want to start the replication daemons, edit the replication

configuration file at/etc/vx/vxfs_repltaband set

VXFS_REPLICATION_START=1 . The replication daemon, by default uses TCP

port 56987. If this port is not free in the environment, specify a desired port in

VXFS_REPLICATION_TGT_PORT=port number.To stop the replication scheduler and the target daemon, run the following

command:

# etc/init.d/vxfs_replication stop

To start the vxfstaskd schedulerdaemon manually, type the followingcommand

on the source system:

Administering Veritas File ReplicatorStarting the vxfstaskd and vxfsrepld daemons

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# vfradmin startsched

Tostopthe vxfstaskd daemon, typethe following commandon thesourcesystem:

# vfradmin stopsched [-f]

The vfradmin stopschedcommand stops the scheduler process after all the in

progress replication jobs are complete. If the-foption is specified, all currently

scheduled replication jobs are aborted. Specifying the -foption may leave the

file system Storage Checkpoints mounted and may leave the target file system in

an intermediate state.

Thevxfsreplddaemon must be running on the systems that function as

replication targets. This daemon listens on the replication port and applies the

delta changes sent by the source system. The vxfsrepld daemon must be started

on the target system before a replication job can be started.

To start thevxfsrepldreplication target daemon manually, type the following

command on the target system:

# vfradmin startvxfsrepld [-p port]

whereportspecifies the port on which the vxfsreplddaemon will listen for the

incoming connection.

Note:By default, the replication daemon uses port 56987. If this port is not free

in theenvironment, you must specifya different port number, using the-p option.

To stopthe vxfsrepld daemon, type thefollowing command on thetarget system:

# vfradmin stopvxfsrepld [-f]

Thevfradmin stopvxfsrepldcommand stops thevxfsreplddaemon after all

the in-progress replication jobs are complete. If the-foption is specified, all in

progress replication jobs are aborted. This may result in a file system in an

intermediate state.

Note:If either daemon processes are killed, they must be manually re-started

using the init script or thevfradmincommand.

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Creating a replication jobTo create a replication job, you must configure the replication job on both the

source and target systems with the same parameters. The vfradmin createjobcommand creates the configuration for the replication job. However, it does not

start the replication automatically. You must specify the -s option when creating

the replication job on the source system and the -toption when creating the

replication job on the target system.

Note:When creating a new replication job, the target file system must be empty,

otherwise the full-sync of the replication job will fail.

To create a replication job, use the following command on both the source and

target systems:

# vfradmin createjob [-p tgt_port] [-s|-t] [-d 0|1] [-c none|xor] name \

src_addr src_mnpt tgt_addr tgt_mntpt freq

where:

tgt_portis the target port. If no port is specified, the default port 56987 is used.

The replication target daemon must be running with the same port, otherwise

the replication job will fail with a "connection refused" error.

nameis the name of the replication job you are creating.

src_addris the IP address or DNS name of the source system. This address is used

as the source for connections.

src_mntptis the mount point on the source system.

tgt_addris the IP address or DNS name of the target system.

tgt_mntptis the mount point on the target system.

freqis the frequency in which the replication job runs. The fre

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