Veritas™ File System 5.0.1 Administrator's Guide

<FILE_PLACEMENT_POLICY Version="5.0">
<RULE Name="GeneralRule">
<SELECT>
<PATTERN>*</PATTERN>
</SELECT>
<CREATE>
<ON>
<DESTINATION>
<CLASS>tier2</CLASS>
</DESTINATION>
</ON>
</CREATE>
other_statements
</RULE>
<RULE Name="DatabaseRule">
<SELECT>
<PATTERN>*.db</PATTERN>
</SELECT>
<CREATE>
<ON>
<DESTINATION>
<CLASS>tier1</CLASS>
</DESTINATION>
</ON>
</CREATE>
other_statements
</RULE>
</FILE_PLACEMENT_POLICY>
The GeneralRule rule specifies that all files created in the file system, designated
by <PATTERN>*</PATTERN>, should be created on tier2 volumes. The DatabaseRule
rule specifies that files whose names include an extension of .db should be created
on tier1 volumes. The GeneralRule rule applies to any file created in the file
system, including those with a naming pattern of *.db, so the DatabaseRule rule
will never apply to any file. This fault can be remedied by exchanging the order
of the two rules. If the DatabaseRule rule occurs first in the policy document,
VxFS encounters it first when determining where to new place files whose names
follow the pattern *.db, and correctly allocates space for them on tier1 volumes.
For files to which the DatabaseRule rule does not apply, VxFS continues scanning
the policy and allocates space according to the specification in the CREATE
statement of the GeneralRule rule.
177Dynamic Storage Tiering
File placement policy rule and statement ordering