RE: RMAN duplicate only used blocks?

From: <>
Date: Tue, 28 Jun 2011 12:17:18 -0400
Message-ID: <>

I don't believe there is any such feature. Notice the words "I believe" :-)

What I believe is available in 11G is that RMAN is capable of backing up only used blocks

But in 1 iTB file if only 200M is used then my understanding will be that somehow magically the output file will still be 1TB even though only 200MB was backed up.

Of course I have not tested it yet.  


[] On Behalf Of Guillermo Alan Bort Sent: Tuesday, June 28, 2011 11:51 AM
To: oracle-l-freelists
Subject: RMAN duplicate only used blocks?  

So, the situation is this, I have a tablespace with about 600GB of free space (spread out in about 80 datafiles). The entire database itself has about 2TB and we need to copy it to another server. The problem is that we have 1.5TB allocated in the ASM instance in the destination server. We wanted to use RMAN, but the database won't fit. We could use export/import but it would take too long and we don't have anywhere to store the export.

Someone pointed to me that RMAN was capable of duplicating only the used blocks... I researched a lot but I couldn't find it... so I'm either looking in the wrong place or that someone was wrong. (there is also the possibility that I'm very sleepy).

I know rman can compress backups and that it only backs up used blocks (when doing a backupset anyway) but I think duplicate just... duplicates... I don't think it resizes and moves stuff around.

Anyway... I think we will have to go with datapump for this one (we are on 11g anyway), but I was just wondering if I was missing a key feature in rman...


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Received on Tue Jun 28 2011 - 11:17:18 CDT

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