
Both basic and subsystem specific migration policies are created and managed using the Migration  
Policies window. The basic policy must be created before creating any subsystem specific  policies.
The fields in the basic policy are displayed with default values. Change any fields  to desired values as 
needed. Click on the Add button to write the new basic policy to the HPSS metadata. 
To configure a subsystem specific policy, select an existing basic policy and click on Configur e. The 
basic policy will be displayed in a tabbed window with a tab for each storage subsystem for which  
subsystem specific thresholds have been created.  Click on the tab for the desired s torage subsystem and 
make the necessary subsystem specific changes, and then click on the Update button.  To add a specific  
threshold configuration for a new subsystem, click the New Subsystem Policy but ton.
When a migration policy is added to an existing storage class, the Migration  Purge Servers for 
that storage class must be restarted in order for the policy to take e ffect.
When HPSS needs to apply a migration policy to a subsystem, it first searches for a matching subsystem 
policy. If none is found, HPSS uses the basic policy. You can consider the basic policy to be the  default 
for all subsystems which do not have policies of their own.
If a policy has one or more subsystem-specific overrides, the basic and subsystem-specific policies will 
be listed separately. Each entry will have the same ID, but the Subsystem field will be blank for  the basic 
policy and contain the subsystem ID for each subsystem-specific override.
After changing any migration policy information, the changes will take effect for each Migration Purge 
Server (MPS) when the MPS is restarted, or when it rereads the changed policy.
Field Descriptions
Policy ID. The unique ID number assigned to this migration policy.
Policy Name. The name assigned to this migration policy.
Subsystem. If the policy is a subsystem-specific override, this shows the subsystem to which it applies. 
This field will be blank for basic policies.
HPSS Management Guide November 2009
Release 7.3 (Revision 1.0) 181