Veritas Volume Manager 5.0 Administrator's Guide (September 2006)

Chapter
6
Creating and administering
plexes
This chapter describes how to create and maintain plexes. Plexes are logical groupings of
subdisks that create an area of disk space independent of physical disk size or other
restrictions. Replication (mirroring) of disk data is set up by creating multiple data plexes
for a single volume. Each data plex in a mirrored volume contains an identical copy of the
volume data. Because each data plex must reside on different disks from the other plexes,
the replication provided by mirroring prevents data loss in the event of a single-point disk-
subsystem failure. Multiple data plexes also provide increased data integrity and
reliability.
Note: Most VxVM commands require superuser or equivalent privileges.
Creating plexes
Note: Plexes are created automatically if you use the vxassist command or the Veritas
Enterprise Administrator (VEA) to create volumes. For more information, see “Creating a
volume” on page 230.
Use the
vxmake command to create VxVM objects, such as plexes. When creating a plex,
identify the subdisks that are to be associated with it:
To create a plex from existing subdisks, use the following command:
# vxmake [-g diskgroup] plex plex sd=subdisk1[,subdisk2,...]
For example, to create a concatenated plex named vol01-02 from two existing subdisks
named mydg02-01 and mydg02-02 in the disk group, mydg, use the following
command:
# vxmake -g mydg plex vol01-02 sd=mydg02-01,mydg02-02