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.