Restarting DUPLICATE After a Failure

RMAN automatically optimizes a DUPLICATE command that is a repeat of a previously failed DUPLICATE command. The repeat DUPLICATE command notices which data files were successfully copied earlier and does not copy them again. This applies to all forms of duplication, whether they are backup-based (with or without a target connection) or active database duplication. The automatic optimization of the DUPLICATE command can be especially useful when a failure occurs during the duplication of very large databases.

To restart a DUPLICATE operation:

1. Exit RMAN.
2. Start SQL*Plus and connect to the auxiliary instance with SYSDBA or SYSBACKUP privilege. Start the auxiliary instance in NOMOUNT mode with the same SPFILE or PFILE specification that you used initially. If you omitted this specification initially, then omit it again here.

This example starts the auxiliary instance using the parameters in /home/my_pfile.ora:

STARTUP FORCE PFILE=/home/my_pfile.ora

1. Exit SQL*Plus and start RMAN.
2. Connect to the same databases as initially
3. Repeat the DUPLICATE command.

The second DUPLICATE operation:

1. Locates the data files that were successfully duplicated by the initial DUPLICATE command.
2. Displays a message similar to the following for each data file that it does not need to duplicate again:

RMAN-05560: Using previous duplicated file /oradata/new/data01.f for datafile 1 with checkpoint SCN of 1654665

1. Restores only the missing or incomplete data files, thereby avoiding recopying and restoring all the data files.

If you do not want RMAN to automatically recover from a failed DUPLICATE operation, specify the keyword NORESUME to disable the functionality. Using the keyword NORESUME in the first invocation of DUPLICATE prevents a subsequent DUPLICATE command for the new database from using this automatic optimization.