Arni, I was confronted with this issue some time ago and the answer I received at that time was TSM was unable to perform "optimized" backups of deduplicated file systems on Win2012. The data gets re-hydrated during backup and more importantly during restore, which may require additional disk space. Support stated then that they were unaware on any plans on the table to address the issue.
Rick Adamson -----Original Message----- From: ADSM: Dist Stor Manager [mailto:ADSM-L@VM.MARIST.EDU] On Behalf Of Arni Snorri Eggertsson Sent: Sunday, May 03, 2015 9:54 AM To: ADSM-L@VM.MARIST.EDU Subject: [ADSM-L] Windows 2012R2 Deduplication Hi all, I have a question about how you should handle backups when running File system de-duplication in Windows, I have a customer who runs Hyper-V, one guest in this HyperV setup is a file server, with disks to big to handle with TSM for HyperV, so that is not an option (not that I think it should be used against file servers), Now the customer has decided that to run data de-duplication inside Windows to lower requirements for disk storage, as far as I can tell TSM does not have any API interface with Windows to handle this, which means that files need to be hydrated during backup. This is very time consuming, and I am worried what happens when we need to restore, (in time perspective) as well as we need to have disk space for fully de-duplicated storage during the restore process. Also after the customer decided to activate file system de-duplication TSM client assumed all the files had changed, so right now we are taking a full backup of the entire file server, does anyone know what happens next time we run incremental backups, can I assume that TSM will take full backups every time or? Does IBM have any plans for supporting this dedup feature in Windows? it's been in Windows 2012R2 since it was released, so I would assume that there are people using it out there, or does the customer need to find alternative ways to solve this. Thanks in advance, --- Arni