On primary storage, EMC has leveraged deduplication across its entire portfolio for a number of years. However whether on EMC or any other vendor, deduplication on primary storage, or target based deduplication, simply doesn't produce the amount of deduplication ratios as source.
I posted a simple explanation of these differences here, so that you can have this conversation with your internal teams:
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For backing up VMware environments, many of our customers are saying source-based deduplication brings the greatest return, providing them in some cases up to 500:1 deduplication, but even more importantly for some customers, the ability to consolidate more VM's onto their ESX servers. Finally, what we find is rarely do customers have their VMware infrastructure in a single data center, but they have smaller VMware environments in remote offices.
As a result, most of my customers acknowledge that source based, global deduplication strategy is appropriate.
For a short demonstration of Avamar's simple, easy approach to easy backup and restore take a look at this short demo:
Download Avamar_VMworld_Final