Dvy,

First, I'm assuming that you are referring to 'optimization' - as the
blob - de-duping / single instance storage right?

Inside the Centera - lot's of misunderstanding about what is de-duped
and what isn't.
CDFs are never duplicated.

Blobs even though the same, are stored in Centera as duplicates if -
they are embedded in a CDF, or the naming scheme used is anything
other than M or M++. GM naming kinda does sometimes - depending on
parameters. Lot's of machines - configed so that de-duping doesn't
occur.

If the app does anything with the blob - it can mess up de-dupe.
(i.e. Legato EX and Symantec EV put data into a container, and even
though objects in the container are the same - Centera can't de-dupe
them.

All that being said, and assuming that you've got dupe data in the
Centera, that has been de-duped by the Centera - when it goes to tape,
with either of the EMC tools for backing up a Centera (CASBAR or
CBRM), your data will be re-populated. That is any effect of de-
duping is removed.

At StorageSwitch, we have some tools for BU of a Centera, that are
currently in test, that will give you the option of maintaining the de-
dupe, or not. Feel free to give me a shout if you have any questions
clark @ storageswitch . com.



On Jan 30, 9:19 am, wrote:
Hi,
When I back data up from an EMC Centera system, is the data on tape
also optimized using the content addressing scheme?

Dvy