Veritas Storage Foundation 5.1 SP1 Advanced Features Administrator"s Guide (5900-1503, April 2011)

Table 27-1
A conceptual comparison of LVM and VxVM (continued)
DescriptionVxVM termLVM term
VxVM can place a disk under its
control without adding it to a disk
group. The VxVM Storage
Administrator shows these disks as
“free space pool”.
LVM contains unused physical extents
that are not part of a logical volume,
but are part of the volume group.
Similarly, free space is an area of a
disk under VxVM that is not allocated
to any subdisk or reserved for use by
any other Volume Manager object.
Free spaceUnused physical extent
Both LVM and VxVM support mirrors.
Mirrors can be used to store multiple
copies of a volume’s data on separate
disks.
In LVM, you can create mirrors using
the MirrorDisk/UX product. Mirrors
allow duplicate copies of the extents
to be kept on separate physical
volumes.
A VxVM mirror consists of plexes.
Each plex is a copy of the volume. A
plex consists of one or more subdisks
that are located on one or more disks.
VxVM volumes can have up to 32
mirrors (where each plex is a copy of
data).
Mirrors (plexes)Mirrors
In LVM, exporting removes volume
group information from /etc/lvmtab.
The volume group must have already
been deactivated.
Similarly in VxVM, deport makes a
disk group inaccessible by the system.
DeportExport
Offline data migration
About VxVM and LVM
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