Veritas Storage Foundation 5.1 SP1 Advanced Features Administrator"s Guide (5900-1503, April 2011)

allocating and relocating files are expressed in the file system's file placement
policy.
A VxFS file placement policy defines the desired placement of sets of files on the
volumes of a VxFS multi-volume file system. A file placement policy specifies the
placement classes of volumes on which files should be created, and where and
under what conditions the files should be relocated to volumes in alternate
placement classes or deleted. You can create file placement policy documents,
which are XML text files, using an XML editor, a text editor, or Veritas Enterprise
Administrator (VEA).
See the /opt/VRTSvxfs/etc/placement_policy.dtd file for the overall structure
of a placement policy.
See the /opt/VRTSfspro/config/placement_policy.dtd file for the overall
structure of a placement policy.
File placement policy rules
A VxFS file placement policy consists of one or more rules. Each rule applies to
one or more files. The files to which a rule applies are designated in one or more
SELECT statements. A SELECT statement designates files according to one or more
of four properties: their names or naming patterns, the directories in which they
reside, their owners' user names, and their owners' group names.
A file may be designated by more than one rule. For example, if one rule designates
files in directory /dir, and another designates files owned by user1, a file in /dir
that is owned by user1 is designated by both rules. Only the rule that appears
first in the placement policy applies to the file; subsequent rules are ignored.
You can define placement policies that do not encompass the entire file system
name space. When a file that is not designated by any rule in its file system's
active placement policy is created, VxFS places the file according to its own internal
algorithms. To maintain full control over file placement, include a catchall rule
at the end of each placement policy document with a SELECT statement that
designates files by the naming pattern *. Such a rule designates all files that have
not been designated by the rules appearing earlier in the placement policy
document.
Two types of rules exist: data and ckpt. The data rule type allows SmartTier to
relocate normal data files. The ckpt rule type allows SmartTier to relocate Storage
Checkpoints. You specify the rule type by setting the Flags attribute for the rule.
347Administering SmartTier
File placement policy rules