This paragraph was taken from Oracle9i RMAN user's guide:
The benefit of performing multilevel incremental backups is that RMAN 
does not back up all blocks all of the time. _/Since RMAN needs to read 
all of the blocks of the datafile, full backups and incremental backups 
take approximately the same amount of time./_
Incremental backups at levels greater than zero only copy blocks that 
were modified. The size of the backup file depends solely upon the 
number of blocks modified and the incremental backup level.
---

Using Advance client and enable BLI along with oracle backup type to 
take incremental backup:
Does it reads the entire file or only read the blocks changed? I'm 
asking in term of "read" the files during backup.
I understood that in term of backup, it only backed up those blocks that 
have been changed.

If the using of Advance Client/BLI within oracle incremental backup 
still read the entire file during the backup, what is the benefit of 
using Advance Client??



Kai Stian Olstad wrote:
> Weber, Philip wrote:
>> Priatna wrote:
>>> If we are using Advance Client along with Oracle agent to take RMAN 
>>> incremental backup, does it _reads the entire file_ or it reads only 
>>> the blocks that have changed? I didn't find the answer on the document.
>>
>> I believe so.  If you use rman to take an Oracle incremental level 1+ 
>> backup, Oracle does the work to work out what data to send.  It sends 
>> its data over the SAN rather than IP which should improve 
>> performance.  If you use block level incremental backups then it 
>> should improve performance by only reading the changed blocks.  
>> That's my understanding anyway.
>
> RMAN incremental backup only takses backup of the changed blocks not 
> the entire file.
>
> A level 0 incremental backup captures all the blocks in the datafiles. 
> A level 1 incremental only captures the blocks that has been changed.
> The level 1 can be cumulative or diffrensial.
>
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: 
http://mailman.eng.auburn.edu/pipermail/veritas-bu/attachments/20070419/ba64bc42/attachment.html