Recent government directives require critical data to be retained for fixed periods of time and to be protected from premature deletion. TSM data retention protection provides fixed retentions for archived objects and prevents the data from being deleted until the retention expires. A TSM server uses data retention protection if the TSM server Archive retention protection status is set to yes.
If a TSM server is enabled for data retention protection, it can only be used to store archive objects because archive copy groups are the only objects which provide a retention attribute. The IBM® Data Retention 450 (DR450) or DR550 servers are customer setup solutions which provide a TSM server pre-configured for data retention protection.
BRMS has been enabled to allow backup or archive operations to be directed to a TSM server enabled for data retention protection. This function is available by PTF in releases prior to V5R4M0 and is integrated into the BRMS TSM device support beginning with V5R4M0.
It is important to understand the BRMS client saves all objects from a System i product to the TSM server as backup objects regardless of whether the operation was a BRMS backup or BRMS archive. BRMS stores these saved objects as backup objects on the TSM server so that BRMS can delete the objects when they expire. It is the expiration date in the BRMS history information that determines when the saved objects expire. When you run BRMS maintenance, expired objects are removed from history. If the object was stored on a TSM server, it is also deleted from the TSM server when the object is deleted from BRMS history. The backup copy group in the management class used by BRMS is set up to only keep one version of the object when it is stored on the TSM server, and it is also set up to not keep any versions of deleted objects. This allows BRMS to efficiently manage the storage it uses at the TSM server.
The data retention servers require clients store objects on the server as archive objects so retention attributes of an archive copy group can be applied to the object. If a user attempts to delete the archived object before the retention has expired, the delete attempt is ended. Archived objects on data retention servers can only be deleted after the retention on the object has expired, thus providing object retention protection. In order for the BRMS client to store objects on a data retention servers, the objects need to be sent as TSM archive objects instead of TSM backup objects.
It is important when saving objects to data retention servers to ensure the retention of the BRMS media policy matches the retention of the archive copy group in the TSM management class. This is necessary so the saved items expire in BRMS history concurrently with the expiration of the object by the server. If an object is saved to a data retention server by BRMS, changing the expiration of the object in BRMS history does not affect the retention at the data retention server.
If the BRMS expiration is later than the TSM expiration, the data retention server expires and deletes the object from its own storage. BRMS deletes the object from history when the history expiration occurs. If the object no longer exists at the data retention server when BRMS attempts the delete, the delete from BRMS history will complete successfully.
If the BRMS expiration is earlier than the data retention server expiration, any attempt by BRMS to delete the object from the TSM server fails with exception BRM2327 – Errors occurred removing item from TSM server. Reason code 0248 is listed in the cause of the message. The objects remain in BRMS history until they also expire on the data retention server.