HP-UX System Administrator's Guide: Overview

HP-UX 11i version 3 supports the following volume managers:
LVM The Logical Volume Manager (LVM) is detailed in HP-UX System Administrator’s
Guide: Logical Volume Management. LVM is the default volume manager for
HP-UX 11i.
VxVM The VERITAS Volume Manager (VxVM) has many features, some of which
are not available with LVM or MirrorDisk/UX (the companion product to LVM
that allows you to mirror data onto multiple physical disks).
The version of VxVM that ships with HP-UX is a base version containing a
subset of the features offered in the full version (which requires an additional
license). For complete information about which features are included with the
base version and the full version of VxVM see the VERITAS Volume Manager
Releases Notes corresponding to the version of the VERITAS Volume Manager
you are using.
Both volume managers can co-exist on a server. Each volume manager keeps track of
which disks it is controlling and any given physical disk can only be a controlled by
one volume manager at a time. The utility vxvmconvert can convert an LVM volume
group to a VxVM disk group if you want to migrate a disk from LVM to VxVM for
greater configuration flexibility.
Volume Management Tasks
The specific volume management tasks you will need to perform will vary slightly
depending on which volume manager you choose. For tasks that are common to both
LVM and the VERITAS Volume Manager, the specific commands or interfaces you
will need to use will also vary depending on which volume manager you are using.
Common volume management tasks include:
• Volume Group / Disk Group Tasks
— Creating volume groups (from collections of physical disks)
— Adding physical disk drives to an existing volume group
— Removing physical disk drives from a volume group
— Mirroring data
• Logical Volume / Volume Tasks
— Creating volumes
— Removing volumes
— Resizing volumes (and, if appropriate, the file systems within them)
In both LVM and the VERITAS Volume Manager, one volume group is treated special:
the root volume group. This refers to the volume group that contains the kernel file that
is used for booting the system. It is also where the root file system, the file system
containing the root directory (“/”), resides. The specifics of how the root volume group
is special (how it differs from other volume groups) varies depending on which volume
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