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5 Replies Latest reply: May 27, 2013 6:29 PM by SAML. RSS

Why do we need a connection to the Source DB for RMAN DUPLICATE ?

Omega3 Newbie
Currently Being Moderated
Version Info: 11.2.0.3/RHEL 5.8

We want to clone a Production DB to a test DB.

Prod DB size: 100gb

We are going to take an RMAN full backup (Hot Backup which includes Archivelogs ) and scp the backup pieces to the Test DB server.

In the Test server , we will be running RMAN DUPLICATE command after connecting like below
rman target sys/passwd@SID_OF_SOURCE_DB auxiliary /
We have everything we need in test server to do the cloning ie. all the RMAN Backup pieces. Then why does RMAN connect to the source DB ?
  • 1. Re: Why do we need a connection to the Source DB for RMAN DUPLICATE ?
    swapnil kambli Journeyer
    Currently Being Moderated
    from [url http://docs.oracle.com/cd/E11882_01/backup.112/e10643/rcmsynta020.htm] here
    Backup-based duplication without a target connection
    
    RMAN creates duplicate files from pre-existing RMAN backups and copies. The DUPLICATE command must have been issued with the DATABASE clause. This form requires a connection to an auxiliary instance and a recovery catalog.
    
    This mode is useful when the target database is not available or a connection to it is not desirable (as mandated by security policy restrictions or a firewall).
    Backup-based duplication without connection to target and recovery catalog
    
    RMAN creates duplicate files from RMAN backups and copies that were placed in a designated BACKUP LOCATION.
    http://dbaregistry.blogspot.com/2011/04/rman-duplicate-without-connecting-to.html

    Edited by: swapnil kambli on May 21, 2013 1:36 AM
  • 2. Re: Why do we need a connection to the Source DB for RMAN DUPLICATE ?
    rarain Explorer
    Currently Being Moderated
    Hi,

    From 11g onwards it is not necessary to connect with target database to duplicate the database using existing backup that means you can run RMAN duplicate command without connecting with target and catalog as well. Here is one of sample script for backup based duplication without connecting to target database:-

    run{

    set newname for database to '/database1/testdb/%b';

    duplicate target database to testdb

    backup location '/database1/rmanbkp'

    LOGFILE

    GROUP 1('/database1/testdb/redo11.log',

    '/database1/testdb/redo12.log') SIZE 20M REUSE,

    GROUP 2('d/database1/testdb/redo21.log',

    '/database1/testdb/redo22.log') SIZE 20M REUSE;

    }

    For more information you can refer below link:-

    http://docs.oracle.com/cd/E11882_01/backup.112/e10642/rcmdupdb.htm#BRADV435

    Thanks
  • 3. Re: Why do we need a connection to the Source DB for RMAN DUPLICATE ?
    Omega3 Newbie
    Currently Being Moderated
    Thank you both.

    But , I still don't get why RMAN has to connect to the source DB when we already have the source DB's full backup available locally.
  • 4. Re: Why do we need a connection to the Source DB for RMAN DUPLICATE ?
    Hemant K Chitale Oracle ACE
    Currently Being Moderated
    Umm. Did you read the two responses ? Both of them show how you do NOT need to connect to the target (i.e. the source) database.

    Hemant K Chitale
  • 5. Re: Why do we need a connection to the Source DB for RMAN DUPLICATE ?
    SAML. Explorer
    Currently Being Moderated
    Hi,

    Before 11g, RMAN cannot read backup piece directly so it has to connect to target database to read that information.

    Cheers,
    SAM L.

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