As with all questions like this, the answer is "it depends".
 It depends on the make-up of your data (# of DB full dumps, % of DB
dumps to filesystem data, % of change on the client, etc)
It depends on the vendor of DeDupe you are using.

FWIW, I am about to replace a 100TB of LTO tape with a DataDomain 560
dedupe box starting next week. Once the migration from tape to disk is
complete, I will be reporting what I saw in my environment. The DD folks
are saying that the worst case scenario will be a 7X reduction (i.e.
70TB of data squeezed into a 10TB DataDomain appliance). We shall see.

Ben
 

-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of
lamont
Sent: Wednesday, January 23, 2008 1:29 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: [ADSM-L] Data Deduplication

Hi,
What would likely be the de-dupe ratio if tsm clients do archive
processing daily (file level, no tdps) with encryption enabled?

Thanks.

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