Veritas Volume Manager 5.1 SP1 Administrator"s Guide (5900-1506, April 2011)

The following command confirms that the vxfs.placement_class tag has been
updated.
# vxassist -g dg3 listtag
TY NAME DISKGROUP TAG
=========================================================
v vol4 dg3 vxfs.placement_class.tier2
Creating a volume using vxmake
As an alternative to using vxassist, you can create a volume using the vxmake
command to arrange existing subdisks into plexes, and then to form these plexes
into a volume.
See “Creating subdisks” on page 272.
The example given in this section is to create a RAID-5 volume using vxmake.
Creating a RAID-5 plex for a RAID-5 volume is similar to creating striped plexes,
except that the layout attribute is set to raid5. Subdisks can be implicitly
associated in the same way as with striped plexes. For example, to create a
four-column RAID-5 plex with a stripe unit size of 32 sectors, use the following
command:
# vxmake -g mydg plex raidplex layout=raid5 stwidth=32 \
sd=mydg00-01,mydg01-00,mydg02-00,mydg03-00
Note that because four subdisks are specified, but the number of columns is not
specified, the vxmake command assumes a four-column RAID-5 plex and places
one subdisk in each column. Striped plexes are created using the same method
except that the layout is specified as stripe. If the subdisks are to be created and
added later, use the following command to create the plex:
# vxmake -g mydg plex raidplex layout=raid5 ncolumn=4 stwidth=32
If no subdisks are specified, the ncolumn attribute must be specified. Subdisks can
be added to the plex later using the vxsd assoc command.
See “Associating subdisks with plexes” on page 275.
If each column in a RAID-5 plex is to be created from multiple subdisks which
may span several physical disks, you can specify to which column each subdisk
should be added. For example, to create a three-column RAID-5 plex using six
subdisks, use the following form of the vxmake command:
Creating volumes
Creating a volume using vxmake
324