VERITAS Volume Manager 3.5 Administrator's Guide (September 2002)

Using vxassist
162 VERITAS Volume Manager Administrator’s Guide
Assisted operations are performed primarily through the vxassist command or the
VERITAS Enterprise Administrator (VEA). vxassist and the VEA create the required
plexes and subdisks using only the basic attributes of the desired volume as input.
Additionally, they can modify existing volumes while automatically modifying any
underlying or associated objects.
Both vxassist and the VEA use default values for many volume attributes, unless you
provide specific values. They do not require you to have a thorough understanding of
low-level VxVM concepts, vxassist and the VEA do not conflict with other VxVM
commands or preclude their use. Objects created by vxassist and the VEA are
compatible and inter-operable with objects created by other VxVM commands and
interfaces.
For more information about the VEA, see the VERITAS Volume Manager (UNIX) User’s
Guide — VEA.
Using vxassist
You can use the vxassist command to create and modify volumes. Specify the basic
requirements for volumecreation ormodification, and vxassist performs the necessary
tasks.
The advantages of using vxassist rather than the advanced approach include:
◆ Most actions require that you enter only one command rather than several.
◆ You are required to specify only minimal information to vxassist. If necessary, you
can specify additional parameters to modify or control its actions.
◆ Operations result in a set of configuration changes that either succeed or fail as a
group, rather than individually. System crashes or other interruptions do not leave
intermediate states that you have to clean up. If vxassist finds an error or an
exceptional condition, it exits after leaving the system in the same state as it was prior
to the attempted operation.
vxassist helps you perform the following tasks:
◆ Creating volumes.
◆ Creating mirrors for existing volumes.
◆ Growing or shrinking existing volumes.
◆ Backing up volumes online.
◆ Reconfiguring a volume’s layout online.
vxassist obtains most of the information it needs from sources other than your input.
vxassist obtains information about the existing objects and their layouts from the
objects themselves.