Understanding VERITAS Volume Manager

VERITAS Volume Manager (VxVM) is a storage management subsystem that allows you to manage physical disks as logical devices called volumes. A volume is a logical device that appears to data management systems as a physical disk.

VxVM provides easy-to-use online disk storage management for computing environments and Storage Area Network (SAN) environments. Through support of Redundant Array of Independent Disks (RAID), VxVM protects against disk and hardware failure. Additionally, VxVM provides features that enable fault tolerance and fast recovery from disk failure.

VxVM overcomes physical restrictions imposed by hardware disk devices by providing a logical volume management layer. This allows volumes to span multiple disks.

VxVM provides the tools to improve performance and ensure data availability and integrity. VxVM also dynamically configures disk storage while the system is active.

The following sections of this chapter explain fundamental concepts of VxVM:

• How VxVM Handles Storage Management
• Physical Objects---Physical Disks
• Virtual Objects
• Volume Layouts in VxVM

The following sections introduce you to advanced features of VxVM:

• Online Relayout
• Volume Resynchronization
• Dirty Region Logging (DRL)
• SmartSync Recovery Accelerator
• Volume Snapshots
• FastResync
• Hot-Relocation

Further information on administering VERITAS Volume Manager may be found in the following documents:

• VERITAS Storage Foundation Cross-Platform Data Sharing Administrator's Guide

Provides more information on using the Cross-platform Data Sharing (CDS) feature of VERITAS Volume Manager, which allows you to move VxVM disks and objects between machines that are running under different operating systems.

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  Note    CDS requires a VERITAS Storage Foundation license.

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• VERITAS Storage Foundation Intelligent Storage Provisioning Administrator's Guide

Describes the command-line interface to the VERITAS Intelligent Storage Provisioning (ISP) feature, which uses a rule-based engine to create VxVM objects and make optimal usage of the available storage.

• VERITAS FlashSnap Point-In-Time Copy Solutions Administrator's Guide

Provides guidelines on using the features of the FlashSnapTM software to implement various point-in-time copy solutions for backup, and database replication.

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  Note    VERITAS FlashSnap requires a separate license.

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• VERITAS Volume Manager Troubleshooting Guide

Describes recovery from hardware failure, disk group configuration and restoration, command and transaction logging, and common error messages together with suggested solutions.

• VERITAS Enterprise Administrator Getting Started

Describes how to use the VERITAS Enterprise Administrator --- the graphical user interface to VERITAS Volume Manager. More detailed information is available in the VEA online help.