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

Nonpersistent (temporary) utility field(s) used to manage objects and
communication between different commands and Symantec products.
tutiln field attributes are not maintained on reboot. tutiln fields are
organized as follows:
■ tutil0 is set by VxVM.
■ tutil1 is set by other Symantec products such as Veritas Operations
Manager (VOM) or the Veritas Enterprise Administrator (VEA) console..
■ tutil2 is available for you to set for site-specific purposes.
If a command is stopped in the middle of an operation, these fields may need
to be cleaned up.
tutiln
Subdisk length. This value is a standard Veritas Volume Manager length number.
See the vxintro(1M) manual page.
You can only change the length of a subdisk if the subdisk is disassociated. You
cannot increase the length of a subdisk to the point where it extends past the
end of the disk or it overlaps a reserved disk region on another disk.
len
Comment.comment
For example, to change the comment field of a subdisk named mydg02-01 in the
disk group, mydg, use the following command:
# vxedit -g mydg set comment="subdisk comment" mydg02-01
To prevent a particular subdisk from being associated with a plex, set the putil0
field to a non-null string, as shown in the following command:
# vxedit -g mydg set putil0="DO-NOT-USE" mydg02-01
See the vxedit(1M) manual page.
About plexes
Plexes are logical groupings of subdisks that create an area of disk space
independent of physical disk size or other restrictions. Replication (mirroring) of
disk data is set up by creating multiple data plexes for a single volume. Each data
plex in a mirrored volume contains an identical copy of the volume data. Because
each data plex must reside on different disks from the other plexes, the replication
provided by mirroring prevents data loss in the event of a single-point
disk-subsystem failure. Multiple data plexes also provide increased data integrity
and reliability.
See “About subdisks” on page 272.
Creating and administering subdisks and plexes
About plexes
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