I need to clone my standby database. It can be done using the DUPLICATE FOR STANDBY command according to the oracle documentation. I did not quit understand how it was done. I found an old thread from this forum that gave the example below of how to get it done.

a) ALTER DATABASE BACKUP CONTROLFILE (create a binary backup of your controlfile on your primary)
b) STARTUP MOUNT the cloned database with that backup copy of the primary database and the datafiles from standby datase
c) RECOVER DATABASE USING BACKUP CONTROLFILE; (applying the needed archlogs backed up on your standby)

When i try to backup the controlfile i get the following error message.

SQL> alter database backup controlfile to 'C:\u01\orabkup\okcdbst1' reuse;
alter database backup controlfile to 'C:\u01\orabkup\okcdbst1' reuse
ERROR at line 1:
ORA-01580: error creating control backup file C:\u01\orabkup\okcdbst1
ORA-27038: skgfrcre: file exists
OSD-04010: option specified, file already exists

Can somebody please give me explicity directions on how to do this.Thanks-