4.2.3.7. Migration and Purge Policy Overrides
The migration and purge policies contain two elements, the basic policy and the storage subs ystem
specific policies. This can be seen on the Migration Policy and Purge Policy windows. If a given
migration or purge policy does not contain any subsystem specific policies, then the basic poli cy applies
across all storage subsystems and no other configuration is needed. If it is desired for migration or purge
to behave differently than specified in the basic policy in a given storage subsystem, then a st orage
subsystem specific policy should be created for that subsystem. A subsystem specific policy allows s ome
or all of the values in the basic policy to be overridden for the given storage subsystem. See Secti on
6.4.2: Migration Policy Configuration on page 182 and Section 6.5.2: Purge Poli cy Configuration on
page 190 for more information.
4.2.3.8. Storage Class Thre shold Overrides
The warning and critical thresholds given on the Storage Class Configuration window apply across all
storage subsystems unless specified otherwise. The Subsystem Thresholds button on the Configured
Storage Class list window allows the default thresholds to be overridden for specified storage
subsystems. See Section 6.1.1: Configured Storage Classes Window on page 157 for more information.
4.2.4. Modifying a Storage Subsystem
If modifications are made to an existing Storage Subsystem configuration, the Core Server and the
Migration Purge Server for the subsystem must be recycled.
4.2.5. Deleting a Storage Su bsystem
Always contact HPSS customer support before deleting a subsystem definition. An improperly
deleted subsystem can cause serious problems for an HPSS system.
It is critical that no files or directories exist within a st orage subsystem before it is deleted. It is
important to verify that all of the DB2 metadata tables associated with the storage subsystem
being deleted are empty.
To verify that all files have been removed from the subsystem, perform the following steps:
1. Run the dump_acct_sum utility on the subsystem. Be sure to specify the subsystem ID with the
-s option as this utility defaults to subsystem 1. The output from the utility should indica te that 0
files exist in the subsystem.
2. As a second verification do the following:
A. Run the db2 command line utility program.
B. Connect to the subsystem database (e.g., connect to subsys1).
C. Set the schema (e.g., set schema hpss).
D. Issue the following SQL command:
db2> select count(*) from bitfile
The result of the command should indicate 0 rows in this table.
HPSS Management Guide November 2009
Release 7.3 (Revision 1.0) 81