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

Accessing a volume
As soon as a volume has been created and initialized, it is available for use as a
virtual disk partition by the operating system for the creation of a file system, or
by application programs such as relational databases and other data management
software.
Creating a volume in a disk group sets up block and character (raw) device files
that can be used to access the volume:
block device file for volume vol in disk group dg/dev/vx/dsk/dg/vol
character device file for volume vol in disk group dg/dev/vx/rdsk/dg/vol
The pathnames include a directory named for the disk group. Use the appropriate
device node to create, mount and repair file systems, and to lay out databases that
require raw partitions.
As the rootdg disk group no longer has special significance, VxVM only creates
volume device nodes for this disk group in the /dev/vx/dsk/rootdg and
/dev/vx/rdsk/rootdg directories. VxVM does not create device nodes in the
/dev/vx/dsk or /dev/vx/rdsk directories for the rootdg disk group.
Using rules and persistent attributes to make volume
allocation more efficient
The vxassist command lets you create a set of volume allocation rules and define
it with a single name. When you specify this name in your volume allocation
request, all the attributes that are defined in this rule are honored when vxassist
creates the volume.
When you create rules, you do not define them in the /etc/default/vxassist
file. You create the rules in another file and add the path information to
/etc/default/vxassist. By default, a rule file is loaded from
/etc/default/vxsf_rules. You can override this location in
/etc/default/vxassist with the attribute rulefile=/path/rule_file_name.
You can also specify additional rule files on the command line.
Creating volume allocation rules has the following benefits:
■ Rules streamline your typing and reduce errors. You can define relatively
complex allocation rules once in a single location and reuse them.
■ Rules let you standardize behaviors in your environment, including across a
set of servers.
Creating volumes
Accessing a volume
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