RMAN Duplicate Command and Target Database

[aditya]

Hi Tim,

We need to create an Auxilary instance on to a different Host from a 10gR2 database using RMAN Duplicate command.

We have a Full Backup and Archive Logs Backup on tapes.

We also have Catalog Database.

Referred Document - Oracle Database Backup and Recovery Advanced User's Guide 10gR2 (B14191-02)

Page 13-2 says - For the duplication to work, you must connect RMAN to both the target (primary) database and an auxiliary instance started in NOMOUNT mode.

Page 13-8 says -

Task 5: Mount or Open the Target Database

Before beginning RMAN duplication, connect SQL*Plus to the target database and
mount or open it if it is not already mounted or open. For example, enter:
-- connect to target database
SQL> CONNECT SYS/oracle@trgt AS SYSDBA;
-- mount or open target database
STARTUP MOUNT;


Recovery catalog for RMAN backup [ID 452529.1] says:

The recovery catalog contains information about RMAN operations, including:

+ Datafile and archived redo log backup sets and backup pieces
+ Datafile copies
+ Archived redo logs and their copies
+ Tablespaces and datafiles on the target database
+ Stored scripts, which are named user-created sequences of RMAN commands
+ Persistent RMAN configuration settings

Can you please explain, even with the catalog database having the target database information, for duplication to work why RMAN must connect to Target database (according to 13-2)
and
Why should the target database be open or mounted (according to 13-8)?

Regards,
Aditya.

[Tim...]

Hi.

To be completely honest, I'm not sure why this dependency is there. I guess if it is available, it may get used in preference to the catalog, because the catalog is only as fresh as the last refresh, which the target database is by definition always up to date.

Cheers

Tim...

[aditya]

Thanks Tim for the response.

Regards,
Aditya.

[Tim...]