Mike is right, depending on the vendor. Please note that he works for one of them, so he should know what he's talking about.
Dedupe works at the subfile-level, but not at the block level. (Vendors that "chunk" data up, which isn't all of them, often create chunks that are larger than a block.) Therefore, multiplexing absolutely CAN remove all deduplication capability, depending on the vendor you're using and how the stars line up. With some vendors, it will make your dedupe ratio 1:1. With others, it will not affect it at all. --- W. Curtis Preston Backup Blog @ www.backupcentral.com VP Data Protection, GlassHouse Technologies ________________________________ From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Ed Wilts Sent: Wednesday, April 30, 2008 4:12 PM To: Mike Sparkes Cc: veritas-bu@mailman.eng.auburn.edu Subject: Re: [Veritas-bu] Multiplexing on VTLs On Wed, Apr 30, 2008 at 5:58 PM, Mike Sparkes <[EMAIL PROTECTED]> wrote: if you ever move to de-duplication, the act of multiplexing your backups ruins the ability to detect duplicate blocks. Your de-dupe ratio will be terrible. I don't follow your logic here. Why would multiplexing affect the de-dupe ratio? .../Ed -- Ed Wilts, Mounds View, MN, USA RHCE, BCFP, BCSD, SCSP mailto:[EMAIL PROTECTED] If I've helped you, please make a donation to my favorite charity at http://firstgiving.com/edwilts This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This message contains confidential information and is intended only for the individual named. If you are not the named addressee you should not disseminate, distribute or copy this e-mail.
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