Veritas 4.1 Installation Guide (HP-UX 11i v3, February 2007)

• 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 electronic mail. Hot-relocation also attempts to use
spare disks and free 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 (RAID-5),
redundant copies of data.
• Online Relayout
Online relayout allows you to convert between storage layouts in VxVM, with uninterrupted
data access.
• Volume Snapshot
Volume Snapshots are point in time images of VxVM volumes.
• Dirty Region Logging
Dirty Region logging (DRL) keeps track of the regions that have been changed due to I/O
writes to a mirrored volume. DRL uses this information to recover only those portions of
the volume that need to be recovered thereby speeding up recovery after system crash.
VxVM 4.1 on HP–UX 11i v3
See “Veritas Volume Manager 4.1 Release Notes”, for more information on features supported with
VxVM 4.1 on HP-UX 11i Version 3.
Architecture of VxVM
VxVM operates as a subsystem between the HP-UX operating system and other data management
systems, such as file systems and database management systems. VxVM is layered on top of the
operating system and is dependent on it for the following:
• Physical access to disk
• Device handles
• VM disks
• Multipathing (See “ HP-UX 11i v3 Native Multipathing for Mass Storage“ available at
http://docs.hp.com for more information on HP-UX Native Multipathing.)
14 Product Overview