Four Steps To Create CATALOG DB

Creating A catalog DB is very simple in oracle :-) Please whenever you choose oracle always think that ORACLE is simple user friendly 

1. ---Create a Table Space for Catalog DB
CREATE TABLESPACE "RMAN" 
DATAFILE 'E:\VmWareM\ORCL_DBFILE\rman01.dbf' SIZE 6208K REUSE
AUTOEXTEND ON NEXT 64K MAXSIZE 32767M
EXTENT MANAGEMENT LOCAL
SEGMENT SPACE MANAGEMENT AUTO;

2. -- Create rman schema owner
CREATE USER rman IDENTIFIED BY rman
TEMPORARY TABLESPACE temp 
DEFAULT TABLESPACE rman 
QUOTA UNLIMITED ON rman;

3. Grant necessary permission 
sql:> GRANT connect, resource, recovery_catalog_owner TO rman;


 4.  Connect to Catalog 

 rman catalog=rman/rman@orcl 
RMAN> CREATE CATALOG TABLESPACE "RMAN";

recovery catalog created

C:\Users\mahamudul.hasan>rman target=/ catalog=rman/rman@orcl

Recovery Manager: Release 11.2.0.1.0 - Production on Mon Aug 11 15:18:37 2014

Copyright (c) 1982, 2009, Oracle and/or its affiliates.  All rights reserved.

connected to target database: ORCL (DBID=1380954007)
connected to recovery catalog database

RMAN> REGISTER DATABASE;

database registered in recovery catalog
starting full resync of recovery catalog
full resync complete

RMAN> RUN {
2>   BACKUP DATABASE PLUS ARCHIVELOG;
3>   DELETE NOPROMPT OBSOLETE;
4> }