Chapter 6 HPSS Configuration
286 September 2002 HPSS Installation Guide
Release 4.5, Revision 2
basic policy. Change the desired fields in the subsystem specific policy and then use theAdd
Specific button to write the new subsystem specific policy to the metadata file.
To update an existing basic purge policy, select theLoad Existing button on the Basic Policy
portionof the Purge Policy window and select the desired policy from the popup list. The window
will be refreshed with the configured basic policy data. After modifying the basic policy, click on
theUpdate Basic button (which is only visible when no subsystem specific policy is selected) to
writethe changes to the metadata file. To update an existing subsystem specific purge policy, first
selectand load the existing basic policy as described above. Then use the Load Existing button and
popuplist on the Storage Subsystem- Specific Policy portion of the Purge Policy window to load
thedesired subsystem specific purge policy.After modifying the subsystem specific policy, click on
theUpdate Specific button (which is only visible when a subsystem specific policy is selected) to
write the changes to the metadata file.
Todelete an existing purge policy,first delete all of the subsystem specific policies, and then delete
the basic policy. Use theLoad Existing button and popup list on the Basic Policy portion of the
screento select the overall policy to be deleted. Next, use the Load Existing button and popup list
onthe Storage Subsystem-Specific Policy portion of the screen to select the first of the subsystem
specific policies to be deleted. Use theDelete Specific button (which is only visible after a
subsystemspecific policy has been selected) to delete each of the subsystem specific policies in turn.
Finally, use theDelete Basic button (which is only visible when no subsystem specific policy is
selected) to delete the basic purge policy.
Before deleting a basic purge policy, make sure that it is not referenced in any storage class
configurations.If a storage class configuration references a purge policy which does not exist,
the Migration/Purge and Bitfile Servers will not start.
When a purge policy is added to or removed from a storage class configuration, the
Migration/Purge Servers must be restarted in order for purge to begin or end on this storage class. It is not
possiblefor MPS to reread a purge policy for a storage class if the purge policy was not assigned to the storage
class when the MPS was started. Likewise, if a purge policy is removed from a storage class configuration,
rereadingthe purge policy for this storage class will not cause the MPS to stop purge this storage class. It is
necessaryto recycle the Migration/Purge Servers when a storage subsystem specific purge policy is added or
removed.It is also necessary to recycle when a storage class configuration is changed to use a different purge
policy.
Before changes made to a purge policy take effect, the Migration/Purge Servers must be either restarted or
instructed to reread the policy from the MPS Storage Class Information window. If the Migration/Purge
Servers are restarted, the changes to the purge policy are applied to all storage classes which reference the
policy.If the policy is reread, the changes are only applied to the storage class and storage subsystem for which
the policy is reread. Bitfile Servers are not able to reread purge policies. If thePurge By field is changed on
either a basic or subsystem specific purge policy, the relevant Bitfile Servers must be restarted.
When a purge policy is added to or removed from a storage class configuration, the Bitfile Servers must be
restartedin order for this change to take effect. If the Bitfile Servers are not restarted after a purge policy has
beenadded to a storage class configuration, purge records will not be created for files written into the storage
class. These files will never be able to purge even after the Bitfile Servers are restarted. If the Bitfile Servers
arenot restarted after a purge policy has been removed from a storage class configuration, purge records will
continue to be created for files written into this storage class. These purge records will become orphaned
metadata since purge is no longer supported on this storage class. It is also necessary to restart the Bitfile
Serversif a storage class configuration is changed to use a different purge policy. It is not necessary to restart
the Bitfile Servers if a storage subsystem specific purge policy is added or removed.