HP-UX Logical Volume Manager and MirrorDisk/UX Release Notes (March 2008)

Logical Volume Manager and MirrorDisk/UX Release Notes
About this Document
This document provides information about the Logical Volume Manager (LVM) and
MirrorDisk/UX products in the March 2008 release of HP-UX 11i v3.
LVM and MirrorDisk/UX Overview
Logical Volume Manager (bundle BaseLVM) is the HP-UX default Volume Manager. It provides
the user with flexibility in configuring and managing mass storage resources. In HP-UX 11i v3,
the LVM kernel and commands are bundled with the core HP-UX product.
MirrorDisk/UX (bundle B2491BA) is an optionally purchased HP-UX product to enable LVM
mirroring functionality.
Overview of Changes
The initial HP-UX 11i v3 release of LVM and MirrorDisk/UX was integrated with the new mass
storage stack, delivering significant performance, scalability, availability, and usability
enhancements. LVM was enhanced to support larger logical volumes, temporary quiescing of
volume groups, and striping with mirroring. Operations that previously required deactivation
or re-creation of a volume group—such as replacing a disk, resizing a LUN, and modifying
volume group characteristics—can now be performed online.
The March 2008 release of LVM and MirrorDisk/UX extends the limits of mass storage, supporting
much larger volume groups, logical volumes, and physical volumes, more mirrors, and simplified
volume group creation.
New and Changed Features in This Release
New Features
The following LVM features are new with the March 2008 release of HP-UX 11i v3:
Version 2.0 Volume Groups
LVM and MirrorDisk/UX now support two versions of volume groups.
Version 1.0 is the version supported on all current and previous versions of HP-UX 11i. The
procedures and command syntax for managing Version 1.0 volume groups are unchanged from
previous releases, except for the enhancements described in “Changed Features” (page 8).
When creating a new volume group, vgcreate defaults to Version 1.0.
Version 2.0 enables the configuration of larger volume groups, logical volumes, physical volumes,
and other parameters. This version is transparently integrated with nearly all HP-UX subsystems
and products. Version 2.0 volume groups can coexist with Version 1.0 volume groups on a server,
and are managed exactly like Version 1.0 volume groups, with the following exceptions:
• Version 2.0 volume groups have simpler options to the vgcreate command, as described
in “Creating a Version 2.0 Volume Group” (page 6).
• Version 2.0 volume groups are not recognized on previous releases of HP-UX, including
versions of HP-UX 11i v3 before March 2008.
• Version 2.0 volume groups do not support root, boot, swap, or dump logical volumes. The
lvlnboot and lvrmboot commands display an error message if run on a Version 2.0
volume group.
• Version 2.0 volume groups do not support bootable physical volumes. You cannot add a
physical volume created with pvcreate -B to a Version 2.0 volume group.
About this Document 5