See page 286 in the AIX admin guide Quote:
Attention: By default, the Tivoli Storage Manager server requires that you back up deduplication-enabled primary storage pools before volumes in the storage pool are reclaimed and before duplicate data is discarded. The copy storage pools and active-data pools to which you back up data and copy active data must not be set up for data deduplication. To prevent possible data loss, do not change the default. If you do change the default, reclamation criteria remains unchanged ... ... Attention: You can change the default setting to permit reclamation of primary storage pools that are not backed up. However, there is a remote possibility that changing the default can result in unrecoverable data loss if a data-integrity error occurs. To change the default and permit reclamation of primary sequential-access storage pools that are not backed up, set the value of the DEDUPREQUIRESBACKUP server option to NO. Changing the default does not change the reclamation criteria that you specified for a storage pool. The DEDUPREQUIRESBACKUP server option applies only to primary storage pools. The option does not apply to copy storage pools or active-data pools. Cheers, Thank you, Neil Strand Storage Engineer - Legg Mason Baltimore, MD. (410) 580-7491 Whatever you can do or believe you can, begin it. Boldness has genius, power and magic. From: ADSM: Dist Stor Manager [mailto:ADSM-L@VM.MARIST.EDU] On Behalf Of Alexander Heindl Sent: Wednesday, September 07, 2011 11:19 AM To: ADSM-L@VM.MARIST.EDU Subject: [ADSM-L] confused about deduprequiresbackup Hi, I'm a bit confused about this option. when I set it to no, reclamation on my primary dedup filepool works when set to yes, not. although all data is copied to a copypool. reclamaion on copypool works in both situations... could it have to do with the fact that the copypool is also file device (on a share) with deduplication activated? Regards, Alex Heindl IMPORTANT: E-mail sent through the Internet is not secure. Legg Mason therefore recommends that you do not send any confidential or sensitive information to us via electronic mail, including social security numbers, account numbers, or personal identification numbers. Delivery, and or timely delivery of Internet mail is not guaranteed. Legg Mason therefore recommends that you do not send time sensitive or action-oriented messages to us via electronic mail. This message is intended for the addressee only and may contain privileged or confidential information. Unless you are the intended recipient, you may not use, copy or disclose to anyone any information contained in this message. If you have received this message in error, please notify the author by replying to this message and then kindly delete the message. Thank you.