Veritas Volume Manager 4.1 Administrator's Guide (HP-UX 11i v3, February 2007)

Chapter 6, Creating and Administering Plexes
Copying Plexes
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Copying Plexes
This task copies the contents of a volume onto a specified plex. The volume to be copied
must not be enabled. The plex cannot be associated with any other volume. To copy a
plex, use the following command:
# vxplex [-g diskgroup] cp volume new_plex
After the copy task is complete, new_plex is not associated with the specified volume
volume. The plex contains a complete copy of the volume data. The plex that is being
copied should be the same size or larger than the volume. If the plex being copied is larger
than the volume, an incomplete copy of the data results. For the same reason, new_plex
should not be sparse.
Dissociating and Removing Plexes
When a plex is no longer needed, you can dissociate it from its volume and remove it as
an object from VxVM. You might want to remove a plex for the following reasons:
◆ to provide free disk space
◆ to reduce the number of mirrors in a volume so you can increase the length of another
mirror and its associated volume. When the plexes and subdisks are removed, the
resulting space can be added to other volumes
◆ to remove a temporary mirror that was created to back up a volume and is no longer
needed
◆ to change the layout of a plex
Caution To save the data on a plex to be removed, the configuration of that plex must be
known. Parameters from that configuration (stripe unit size and subdisk
ordering) are critical to the creation of a new plex to contain the same data.
Before a plex is removed, you must record its configuration. See “Displaying
Plex Information” on page 184” for more information.
To dissociate a plex from the associated volume and remove it as an object from VxVM,
use the following command:
# vxplex [-g diskgroup] -o rm dis plex
For example, to dissociate and remove a plex named vol01-02 in the disk group, mydg,
use the following command:
# vxplex -g mydg -o rm dis vol01-02
This command removes the plex vol01-02 and all associated subdisks.