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

requirement for a disk group, each volume created has the allsites attribute set
to on, by default. The allsites attribute indicates that the volume must have at
least one plex on each site that is registered to the disk group. For new volumes,
the read policy is set to siteread.
If site-based allocation is not required, or is not possible (as is the case for RAID-5
volumes), specify the allsites=off attribute to the vxassist command.
Before setting site-based allocation on a disk group, be sure to meet the following
requirements:
■ The Site Awareness license must be installed on all the hosts in the Remote
Mirror configuration
■ Each existing volume in the disk group must have at least one plex at each
site. If this condition is not met, the command to turn on the site-based
allocation fails. If the -f option is specified, the command does not fail, but
instead it sets the allsites attribute for the volume to off.
To turn on the site-based allocation requirement on a disk group
◆
Use the vxdg addsite command for each site at which site-based allocation
is required:
# vxdg -g diskgroup [-f] addsite sitename
To remove the site-based allocation requirement on a disk group
◆
To remove the site-based allocation requirement from a site, use this
command:
# vxdg -g diskgroup [-f] rmsite sitename
The -f option allows the requirement to be removed if the site is detached
or offline.
The site name is not removed from the disks. If required, use the vxdisk
rmtag command to remove the site tag.
See “Configuring Remote Mirror sites” on page 490.
Configuring site consistency on a disk group
Site consistency means that the data in the plexes for a volume must be consistent
at each site. A site-consistent volume has the same number of plexes, or mirrors,
on each site in the disk group. A site-consistent volume must have at least one
plex, or mirror, on each site in the disk group. The site consistency of a volume
is ensured by detaching a site when its last complete plex fails at that site. If a
Administering sites and remote mirrors
Configuring site consistency on a disk group
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