Veritas Volume Manager 5.0.1 Administrator's Guide, HP-UX 11i v3, First Edition, November 2009

Note: The file system must be mounted to get the benefits of the SmartMove™
feature.
When the SmartMove feature is on, less I/O is sent through the host, through the
storage network and to the disks or LUNs. The SmartMove feature can be used
for faster plex creation and faster array migrations.
The SmartMove feature enables migration from a traditional LUN to a thinly
provisioned LUN, removing unused space in the process.
See “Migrating to thin provisioning” on page 577.
Discovering the maximum size of a volume
To find out how large a volume you can create within a disk group, use the
following form of the vxassist command:
# vxassist [-g diskgroup] maxsize layout=layout [attributes]
For example, to discover the maximum size RAID-5 volume with 5 columns and
2 logs that you can create within the disk group, dgrp, enter the following
command:
# vxassist -g dgrp maxsize layout=raid5 nlog=2
You can use storage attributes if you want to restrict the disks that vxassist uses
when creating volumes.
See “Creating a volume on specific disks” on page 283.
The maximum size of a VxVM volume that you can create is 256TB.
Disk group alignment constraints on volumes
Certain constraints apply to the length of volumes and to the numeric values of
size attributes that apply to volumes. If a volume is created in a disk group that
is compatible with the Cross-platform Data Sharing (CDS) feature, the volume’s
length and the values of volume attributes that define the sizes of objects such
as logs or stripe units, must be an integer multiple of the alignment value of 8
blocks (8 kilobytes). If the disk group is not compatible with the CDS feature, the
volume’s length and attribute size values must be multiples of 1 block (1kilobyte).
To discover the value in blocks of the alignment that is set on a disk group, use
this command:
# vxprint -g diskgroup -G -F %align
Creating volumes
Discovering the maximum size of a volume
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