Veritas 5.0.1 Installation Guide, HP-UX 11i v3, First Edition, November 2009

Veritas Volume Manager (VxVM)
Introduction
VxVM is a storage management subsystem that removes the physical limitations of disk storage
so that you can configure, share, manage, and optimize storage I/O performance online without
interrupting data availability. VxVM also provides easy-to-use, online storage management tools
to reduce planned and unplanned system downtime, and online disk storage management for
computing environments and Storage Area Network (SAN) environments. Through RAID
support, VxVM protects against disk and hardware failure. Additionally, VxVM provides features
that offer 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 enables volumes to span multiple disks. VxVM also dynamically
configures disk storage while the system is active.
VxVM Features
Veritas Volume Manager supports the following features:
• Veritas Enterprise Administrator (VEA)
A Java™-based graphical user interface for administering VxVM.
• Concatenation
Concatenation maps data in a linear manner onto one or more subdisks in a plex.
• Striping
Striping maps data, so that data is interleaved among two or more physical disks.
• Mirroring
Mirroring uses multiple mirrors to duplicate information contained in a volume.
• Mirrored Stripes
VxVM supports a combination of mirroring and striping.
• Striped Mirrors
VxVM supports a combination of striping and mirroring.
• RAID-5
RAID-5 provides data redundancy using parity.
• Online Resizing of Volumes
You can dynamically resize VxVM volumes while the data remains available to the user.
• Hot-relocation
The hot-relocation feature in VxVM automatically detects disk failures, and notifies the
system administrators of the failure, by email. Hot-relocation also attempts to use spare
disks and frees disk space to restore redundancy and to preserve access to mirrored and
RAID-5 volumes.
• Volume Resynchronization
Volume resynchronization ensures that all copies of the data match, when mirroring
redundant copies of data.
• Online Relayout
Online relayout enables you to convert between storage layouts in VxVM, with uninterrupted
data access.
14 Introduction