VERITAS Volume Manager 3.1 Migration Guide

Command Differences
Comparison of LVM and VxVM Tasks
Chapter 3 75
VxVM The Multipathing disk devices
in the Volume Manager
represent virtual devices with
one or more physical access
paths to a particular physical
disk. Dynamic Multipathing
provides reliability of disk
access by dynamically switching
to another physical path in the
event of failure of a path.
The DMP feature in VxVM sets up
links automatically. It is not required to
set up links separately.
Refer to the manual page vxdmp (7)
and the VERITAS Volume Manager 3.1
Administrator’s Guide for more
information on DMP.
LVM Create a mirrored logical
volume.
lvcreate -l num_log_extents -m 1
-n mirr_lv /dev/ vol_grp
VxVM Create a mirrored volume/plex
or add a mirror to an existing
volume.
vxassist make vol_namelength
layout=mirrorvxmake
plex plex_namesdisk_name
vxplex att vol_nameplex_name
LVM Reduce a single/double mirrored
logical volume to an unmirrored
logical volume.
Remove a mirrored logical
volume.
lvreduce -m 0
/dev/ vol_grp / mirr_lv
lvremove /dev/ vol_grp / mirr_lv
VxVM Remove mirrors or reduce the
number of plexes/mirrors.
Remove a volume with the
plexes associated with it.
vxplex -o rm dis plex_name
vxedit -rf rm vol_name
LVM Increase the number of mirror
copies.
lvextend -m 2
/dev/ vol_grp / lvol_name
VxVM Add mirrors to a volume or
increase the number of plexes.
vxassist mirror vol_name
Table 3-2LVM and VxVM Task Comparison
Task
Type
Description Example