HP-UX Logical Volume Manager and MirrorDisk/UX Release Notes (September 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 September 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. Volume group availability was improved: resizing
a LUN and modifying volume group characteristics no longer required the volume group to be
recreated, and replacing a disk could be done online.
The September 2008 release of LVM and MirrorDisk/UX continues to extend the limits of mass
storage, supporting a larger number of volume groups, logical volumes, and physical volumes.
This release also allows a volume group to take advantage of LUN expansion online, detects and
corrects problems with the boot disk's hardware path, and displays additional information.
New and Changed Features in This Release
New Features
The following LVM features are new with the September 2008 release of HP-UX 11i v3:
Version 2.1 Volume Groups
LVM and MirrorDisk/UX now support three 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 7).
When creating a new volume group, vgcreate defaults to Version 1.0.
Version 2.0, introduced in the March 2008 release of HP-UX 11i v3, enables the configuration of
larger volume groups, logical volumes, physical volumes, and other parameters. Version 2.1,
introduced in this release, is similar to Version 2.0, but allows an even greater number of volume
groups, physical volumes, and logical volumes. Version 2.1 volume groups can coexist with
Version 2.0 and Version 1.0 volume groups on a server, and are managed exactly like Version
2.0 volume groups, with the following exceptions:
• Version 2.1 volume groups are not recognized on previous releases of HP-UX, including
versions of HP-UX 11i v3 before September 2008.
• Version 2.1 supports up to 2048 volume groups. However, this limit is shared between
Version 2.0 and Version 2.1 volume groups.
*
Table 1 compares the configuration limits of Version 1.0, Version 2.0, and Version 2.1 volume
groups. These limits are independent — for example, a server can be configured with 256 Version
1.0 volume groups and 512 Version 2.0 volume groups at the same time.
About this Document 5