VERITAS Volume Manager 4.1 Administrator's Guide

Creating and Administering Subdisks
Associating Subdisks with Plexes
Chapter 5204
Associating Subdisks with Plexes
Associating a subdisk with a plex places the amount of disk space
defined by the subdisk at a specific offset within the plex. The entire area
that the subdisk fills must not be occupied by any portion of another
subdisk. There are several ways that subdisks can be associated with
plexes, depending on the overall state of the configuration.
If you have already created all the subdisks needed for a particular plex,
to associate subdisks at plex creation, use the following command:
# vxmake plex plex sd=subdisk,...
For example, to create the plex home-1 and associates subdisks
disk02-01, disk02-00, and disk02-02 with plex home-1, use the following
command:
# vxmake plex home-1 sd=disk02-01,disk02-00,disk02-02
Subdisks are associated in order starting at offset 0. If you use this type
of command, you do not have to specify the multiple commands needed to
create the plex and then associate each of the subdisks with that plex. In
this example, the subdisks are associated to the plex in the order they
are listed (after sd=). The disk space defined as disk02-01 is first,
disk02-00 is second, and disk02-02 is third. This method of associating
subdisks is convenient during initial configuration.
Subdisks can also be associated with a plex that already exists. To
associate one or more subdisks with an existing plex, use the following
command:
# vxsd assoc plex subdisk1 [subdisk2 subdisk3 ...]
For example, to associate subdisks named disk02-01, disk02-00, and
disk02-02 with a plex named home-1, use the following command:
# vxsd assoc home-1 disk02-01 disk02-00 disk02-01
If the plex is not empty, the new subdisks are added after any subdisks
that are already associated with the plex, unless the -l option is specified
with the command. The -l option associates subdisks at a specific offset
within the plex.
The -l option is required if you previously created a sparse plex (that is, a
plex with gaps between its subdisks) for a particular volume, and
subsequently want to make the plex complete. To complete the plex,