RMAN Recovery Catalog Setup and Configuration

Configure the Database for RMAN Operations

Set Up the Database User in the target database

create user backup_admin identified by backup_admin default tablespace users;
grant sysdba to backup_admin;

Creating the Recovery Catalog

Creating the Recovery Catalog User

create user rcat_user identified by rcat_user default tablespace users;
grant connect,resource,recovery_catalog_owner to rcat_user;

Creating the Recovery Catalog Schema Objects

Step 1. Connect to the recover catalog with RMAN:
rman catalog=rcat_user/rcat_user@reco
Step 2. Issue the create catalog command from the RMAN prompt:
create catalog;

Register your database in the recovery catalog

Step 1: Using RMAN, sign into the database and the recover catalog at the same time
ORACLE_SID=FKDB; export ORACLE_SID
rman catalog=rcat_user/rcat_user@RECO target=backup_admin/backup_admin
or
ORACLE_SID=RECO; export ORACLE_SID
rman catalog=rcat_user/rcat_user target=backup_admin/backup_admin@FKDB
Recovery Manager: Release 9.2.0.1.0 - 64bit Production
Copyright (c) 1995, 2002, Oracle Corporation. All rights reserved.
connected to target database: RECO (DBID=1308910273)
connected to recovery catalog database
Step 2: Register the database with the recovery catalog
RMAN> register database

Errors Faced
Delete the recovery catalog database, after some days created a new database, but was not able to take backup,
I was getting ora-1580 error

Solution - unregister database
select * from rc_database;
execute dbms_rcvcat.unregisterdatabase (db_key, db_id)