There are certain data that should not be compress again by the client. Files that are already compress. Any backups that are done by the various TDP components.
-----Original Message----- From: ADSM: Dist Stor Manager [mailto:ads...@vm.marist.edu] On Behalf Of Hart, Charles A Sent: Wednesday, January 13, 2010 6:14 AM To: ADSM-L@VM.MARIST.EDU Subject: Re: DataDomain VTL Any "compressed/ encrypted" data will not de-dupe well or if at all. (Compressed / Encrypted Data have unique signatures every time) In regards to client side compression, that feature tends to be of value on a small remote site or if you have a 10Mb lan. You can force the client compression off from the Server side using client option sets. Regards, Charles -----Original Message----- From: ADSM: Dist Stor Manager [mailto:ads...@vm.marist.edu] On Behalf Of Nick Laflamme Sent: Tuesday, January 12, 2010 7:19 PM To: ADSM-L@VM.MARIST.EDU Subject: Re: [ADSM-L] DataDomain VTL On Jan 12, 2010, at 11:27 AM, Kelly Lipp wrote: > We have a customer that insisted on buying one of these for his TSM environment. Promised 20:1 dedup. He saw about five to one. He was in our Level 2 class telling the story. At the end he said he wouldn't buy it again. I made him repeat that part of the story... DataDomain's "Best Practices" guide for TSM tells customers not to let nodes compress data. I have to wonder how much compressing the data or not alters the dedup ratio. I'm not at all sure that we're going enforce a "no compression" policy for our clients. This e-mail, including attachments, may include confidential and/or proprietary information, and may be used only by the person or entity to which it is addressed. If the reader of this e-mail is not the intended recipient or his or her authorized agent, the reader is hereby notified that any dissemination, distribution or copying of this e-mail is prohibited. If you have received this e-mail in error, please notify the sender by replying to this message and delete this e-mail immediately.