Impdp does not created user/schema

Until  now my understanding for EXPDP/IMPDP was that if the user performing import has 'IMPORT FULL DATABASE' privilege, it'll create the users/schemas in the target database. I needed to export (expdp) schema from one machine and import (impdp) it to another machine. I just wanted  impdp to create schema on target database.

While doing  import  i encountered error

$ impdp system/oracle123 directory=TEST_DIR dumpfile=test.dmp logfile=impdptest.log

 .......

Starting "SYSTEM"."SYS_IMPORT_FULL_01":  system/******** directory=TEST_DIR dumpfile=USR_TEST.dmp logfile=impdpUSR_TEST.log

Processing object type SCHEMA_EXPORT/PRE_SCHEMA/PROCACT_SCHEMA

ORA-39083: Object type PROCACT_SCHEMA failed to create with error:

ORA-31625: Schema USR_TEST is needed to import this object, but is unaccessible

ORA-01435: user does not exist

Failing sql is:

BEGIN

sys.dbms_logrep_imp.instantiate_schema(schema_name=>SYS_CONTEXT('USERENV','CURRENT_SCHEMA'), export_db_name=>'XXX.YYY.COM', inst_scn=>'7788478540892');COMMIT; END;

Processing object type SCHEMA_EXPORT/TABLE/TABLE

ORA-39083: Object type TABLE:"USR_TEST"."TABLE1" failed to create with error:

ORA-01918: user 'USR_TEST' does not exist

Failing sql is:

CREATE TABLE "USR_TEST"."TABLE1" ("COLUMN1" VARCHAR2(20 BYTE) NOT NULL ENABLE, "COLUMN2" VARCHAR2(20 BYTE), "COLUMN3" VARCHAR2(20 BYTE)) SEGMENT CREATION IMMEDIATE PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 NOCOMPRESS LOGGING STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAU

Processing object type SCHEMA_EXPORT/TABLE/INDEX/INDEX

Processing object type SCHEMA_EXPORT/TABLE/CONSTRAINT/CONSTRAINT

Job "SYSTEM"."SYS_IMPORT_FULL_01" completed with 2 error(s).

$

After reading some documents,blogs I discovered  that If  the schema you are importing to does not already exist, the import operation creates it, provided the dump file set contains the necessary CREATE USER metadata and you are importing with enough privileges.

Meaning the oracle user that exported the schema, should have had CREATE USER privilege.Export was done with user (USR_TEST) was a basic user and not DBA/create-user-privileged. 

Below query given result as.

SQL>  select  *  from  ROLE_SYS_PRIVS  where  PRIVILEGE = ’CREATE USER’ ;

ROLE                                              PRIVILEGE                     ADM
----------------------------           --------------------              ---

DBA                                               CREATE USER                 YES

IMP_FULL_DATABASE           CREATE USER                  NO

2 rows selected.

It means EXP_FULL_DATABAS role does not have create user privilege.

I did 'GRANT CREATE USER TO USR_TEST' here and  ran the export again and this time some additional "object types" were processed.

 when USR_TEST user didn't have 'CREATE USER' privilege:

 $ expdp USR_TEST/USR_TEST schemas=USR_TEST content=METADATA_ONLY directory=TEST_DIR dumpfile=USR_TEST.dmp logfile=expdpUSR_TEST.log

.......

Starting "USR_TEST"."SYS_EXPORT_SCHEMA_01":  USR_TEST/******** schemas=USR_TEST content=METADATA_ONLY directory=TEST_DIR dumpfile=USR_TEST.dmp logfile=expdpUSR_TEST.log

Processing object type SCHEMA_EXPORT/PRE_SCHEMA/PROCACT_SCHEMA

Processing object type SCHEMA_EXPORT/TABLE/TABLE

Processing object type SCHEMA_EXPORT/TABLE/COMMENT

Processing object type SCHEMA_EXPORT/TABLE/INDEX/INDEX

Processing object type SCHEMA_EXPORT/TABLE/CONSTRAINT/CONSTRAINT

Processing object type SCHEMA_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS

Master table "USR_TEST"."SYS_EXPORT_SCHEMA_01" successfully loaded/unloaded

******************************************************************************

.......

when USR_TEST user  have 'CREATE USER' privilege:

 $ expdp USR_TEST/USR_TEST schemas=USR_TEST content=METADATA_ONLY directory=TEST_DIR dumpfile=USR_TEST.dmp logfile=expdpUSR_TEST.log

.......

Starting "USR_TEST"."SYS_EXPORT_SCHEMA_01":  USR_TEST/******** schemas=USR_TEST content=METADATA_ONLY directory=TEST_DIR dumpfile=USR_TEST.dmp logfile=expdpUSR_TEST.log

Processing object type SCHEMA_EXPORT/USER

Processing object type SCHEMA_EXPORT/SYSTEM_GRANT

Processing object type SCHEMA_EXPORT/ROLE_GRANT

Processing object type SCHEMA_EXPORT/DEFAULT_ROLE

Processing object type SCHEMA_EXPORT/PRE_SCHEMA/PROCACT_SCHEMA

Processing object type SCHEMA_EXPORT/TABLE/TABLE

Processing object type SCHEMA_EXPORT/TABLE/COMMENT

Processing object type SCHEMA_EXPORT/TABLE/INDEX/INDEX

Processing object type SCHEMA_EXPORT/TABLE/CONSTRAINT/CONSTRAINT

Processing object type SCHEMA_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS

Master table "USR_TEST"."SYS_EXPORT_SCHEMA_01" successfully loaded/unloaded

******************************************************************************

.......

Note the Processing object type SCHEMA_EXPORT/USER, SCHEMA_EXPORT/SYSTEM_GRANT, SCHEMA_EXPORT/ROLE_GRANT, SCHEMA_EXPORT/DEFAULT_ROLE.

To avoid such situations always try to take the export using SYSTEM user.

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Identify the Tablespace names from EXPDP dump file

 I got  request from development team to import some old data in UAT region.The expdp dump file received from backup team was without  log file and i have no access to the export file's source DB. I wanted to import that dumpfile into UAT DB and i do not know the tablespace names required to do so.

Solution:

Use the sqlfile option present in impdp utility. This option will write all the SQL DDL to a specified file instead of executing them.

$ impdp scott/tiger directory=exp_dir dumpfile=scott.dmp sqlfile=script.sql

Import: Release 11.1.0.7.0 - 64bit Production on Tuesday, 20 February, 2014 21:34:36

Copyright (c) 2003, 2007, Oracle.  All rights reserved.

Connected to: Oracle Database 11g Enterprise Edition Release 11.1.0.7.0 - 64bit Production

With the Partitioning, OLAP, Data Mining and Real Application Testing options

Master table "SCOTT"."SYS_SQL_FILE_FULL_01" successfully loaded/unloaded

Starting "SCOTT"."SYS_SQL_FILE_FULL_01":  scott/******** directory=exp_dir dumpfile=scott.dmp sqlfile=script.sql

Processing object type SCHEMA_EXPORT/USER

Processing object type SCHEMA_EXPORT/SYSTEM_GRANT

Processing object type SCHEMA_EXPORT/ROLE_GRANT

Processing object type SCHEMA_EXPORT/DEFAULT_ROLE

Processing object type SCHEMA_EXPORT/PRE_SCHEMA/PROCACT_SCHEMA

Processing object type SCHEMA_EXPORT/SEQUENCE/SEQUENCE

Processing object type SCHEMA_EXPORT/TABLE/TABLE

Processing object type SCHEMA_EXPORT/TABLE/INDEX/INDEX

Processing object type SCHEMA_EXPORT/TABLE/CONSTRAINT/CONSTRAINT

Processing object type SCHEMA_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS

Processing object type SCHEMA_EXPORT/PROCEDURE/PROCEDURE

Processing object type SCHEMA_EXPORT/PROCEDURE/ALTER_PROCEDURE

Processing object type SCHEMA_EXPORT/TABLE/TRIGGER

Processing object type SCHEMA_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS

Job "SCOTT"."SYS_SQL_FILE_FULL_01" successfully completed at 21:34:53

The content of the scripts.sql file would be like this.

-- CONNECT SCOTT

ALTER SESSION SET EDITION = "ORA$BASE";

-- new object type path: SCHEMA_EXPORT/USER

-- CONNECT SYSTEM

ALTER SESSION SET EDITION = "ORA$BASE";

 CREATE USER "SCOTT" IDENTIFIED BY VALUES 'S:D846EA3EB87287A3AED08AF38EB0B4F640F49A9A4A972108BF3917B769;DB1B37F84BDF15E6'

      DEFAULT TABLESPACE "USERS"

      TEMPORARY TABLESPACE "TEMP";

-- new object type path: SCHEMA_EXPORT/SYSTEM_GRANT

GRANT UNLIMITED TABLESPACE TO "SCOTT";

-- new object type path: SCHEMA_EXPORT/ROLE_GRANT

 GRANT "DBA" TO "SCOTT";

-- new object type path: SCHEMA_EXPORT/DEFAULT_ROLE

 ALTER USER "SCOTT" DEFAULT ROLE ALL;

-- new object type path: SCHEMA_EXPORT/PRE_SCHEMA/PROCACT_SCHEMA

-- CONNECT SCOTT

ALTER SESSION SET EDITION = "ORA$BASE";

BEGIN

sys.dbms_logrep_imp.instantiate_schema(schema_name=>SYS_CONTEXT('USERENV','CURRENT_SCHEMA'), export_db_name=>'PROD9.DIAMOND.COM', inst_scn=>

'11626845804212');

COMMIT;

END;

/

 .

.

.

.

.

.

After finding all the required tablespaces i used REMAP_TABLESPACE  and then import the dump file .

One can manually create same  tablespaces and import the dump file. 

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ORA-01031: insufficient privileges to sys@standby as sysdba

The ORA-01031 is very generic error and normally users will receive this error when users don’t have appropriate privilege.

$oerr ora 01031
01031, 00000, "insufficient privileges"
// *Cause: An attempt was made to change the current username or password
//         without the appropriate privilege. This error also occurs if
//         attempting to install a database without the necessary operating
//         system privileges.
//         When Trusted Oracle is configure in DBMS MAC, this error may occur
//         if the user was granted the necessary privilege at a higher label
//         than the current login.
// *Action: Ask the database administrator to perform the operation or grant
//          the required privileges.
//          For Trusted Oracle users getting this error although granted the
//          the appropriate privilege at a higher label, ask the database
//          administrator to regrant the privilege at the appropriate label.

On standby
$ sqlplus
Enter user-name: /as sysdba

Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL>


From Primary or Standby
$ sqlplus
 
Enter user-name: sys@standby as sysdba
Enter password:
ERROR:
ORA-01031: insufficient privileges


Error in alert log of PRIMARY database

Error 1034 received logging on to the standby
PING[ARC0]: Heartbeat failed to connect to standby 'STANDBY'. Error is 1034.
Error 1034 received logging on to the standby
FAL[server, ARC2]: Error 1034 creating remote archivelog file 'STANDBY'

 Metalink notes for insufficient privileges  as sysdba
OERR: ORA 1031 "insufficient privileges" [ID 18622.1]
Troubleshooting ORA-1031: Insufficient Privileges While Connecting As SYSDBA [ID 730067.1]

But

Original problem in my case  was with listener file. Instance name is crated in small letter but in listener.ora sid given in CAPS it caused the problem. After changing sid in listner.ora it is working fine.

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Creating Redo Log Groups and Members

Create all required groups and members of redo log files during database creation. However, there are situations where you might want to create additional groups or members.

Creating Redo Log Groups

To create new redo log groups and members, you must have the ALTER DATABASE system privilege.

To create a new group of redo log files, use the SQL statement ALTER DATABASE with the ADD LOGFILE clause.

The following statement adds a new group of redo logs to the database:

 ALTER DATABASE

  ADD LOGFILE ('/oracle/dbs/log1c.rdo', '/oracle/dbs/log2c.rdo') SIZE 500K;

You can also specify the number that identifies the group using the GROUP clause:

ALTER DATABASE

  ADD LOGFILE GROUP 10 ('/oracle/dbs/log1c.rdo', '/oracle/dbs/log2c.rdo')

      SIZE 500K;

Using group numbers can make administering redo log groups easier. However, the group number must be between 1 and MAXLOGFILES.

In some cases, it might not be necessary to create a complete group of redo log files. A group could already exist, but not be complete because one or more members of the group were dropped (for example, because of a disk failure). In this case, you can add new members to an existing group.

Creating Redo Log Members

To create new redo log members for an existing group, use the SQL statement ALTER DATABASE with the ADD LOGFILE MEMBER clause.

The following statement adds a new redo log member to redo log group number 2:

ALTER DATABASE ADD LOGFILE MEMBER '/oracle/dbs/log2b.rdo' TO GROUP 2;

Notice that filenames must be specified, but sizes need not be. The size of the new members is determined from the size of the existing members of the group.

When using the ALTER DATABASE statement, you can alternatively identify the target group by specifying all of the other members of the group in the TO clause, as shown in the following example:

ALTER DATABASE ADD LOGFILE MEMBER '/oracle/dbs/log2c.rdo'

    TO ('/oracle/dbs/log2a.rdo', '/oracle/dbs/log2b.rdo');

Note:

Fully specify the filenames of new log members to indicate where the operating system files should be created. Otherwise, the files will be created in either the default or current directory of the database server, depending upon your operating system. You may also note that the status of the new log member is shown as INVALID. This is normal and it will change to active (blank) when it is first used.

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Multiplex & Move Oracle control files to different directory

1, shutdown database.

shutdown immediate;

2, edit Oracle init.ora file, e.g., C:\Oracle\10g\database\inittest.ora, find the line with control file location, change the location from old directory to new directory, e.g.:

         OLD:
         control_files=("H:\Oradata\test\control01.ctl")

         NEW:
         control_files=("I:\Oradata\test\control01.ctl",  "J:\Oradata\test\control02.ctl", "K:\Oradata\test\control03.ctl")

save init.ora file.

3, create spfile from pfile:

create spfile from pfile;

4, Copy control files from old directory to new directory

    copy H:\Oradata\test\control01.ctl I:\Oradata\test\control01.ctl
    copy H:\Oradata\test\control01.ctl J:\Oradata\test\ control02.ctl
    copy H:\Oradata\test\control01.ctl K:\Oradata\test\control03.ctl

5, startup database.

SQL> startup
ORACLE instance started.
Total System Global Area 1426063360 bytes
Fixed Size 2004264 bytes
Variable Size 352324312 bytes
Database Buffers 1056964608 bytes
Redo Buffers 14770176 bytes
Database mounted.
Database opened.
SQL>

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Automate AWR Report Generation

By default snapshots of the relevant data are taken every hour and retained for 7 days. Most of the times database running in default AWR settings. DBA's generates the awr report when something  happened in their database or periodically to check if anything is wrong in databases

Some times databases are running smooth without any problems. Due to the default retention of AWR snapshot setting we may loose some good information about database.When problem occurs in the database we may need to compare the bad time report (when problem occurred) vs good time report (when db running smooth). In this case we don't have any information about database when running without any problem or we don't have same period snapshot AWR report to compare it with current reports.

To avoid this situation DBA can automate the AWR reports generation using below script.
It automatically generates the awr report of last one hour and no manual intervention is required by DBAs onece it is schedule in cronjob

Crontab Entry

05 * * * * sh /oracle/AWR/generate_awr.sh ORCL  >> /oracle/AWR/awr_rpt.log

Cronjob to be executed every hour at 05 mins on daily basis  and shell output is redirected to log file

SCRIPT STARTS HERE
##############################################################################
1 ) generate_awr.sh

#------------------------------------------------------------------------------
#!/usr/bin/ksh
# File: generate_awr.sh
# Description:
# shell script to run under the UNIX "cron" utility to automatically generate Oracle "AWR" reports in HTML   against the database accessed via passed parameter
# Usage :
# sh generate_awr.sh oracle_sid
# Parameters:
#  One parameter to be  passed. Oracle_sid to be passed as parameter.
#  Environment variables are captured from /etc/oratab entry.

dbSid=${1}

export oraSid=${dbSid}
#echo $oraSid
export ORACLE_SID=`grep "$oraSid:" /etc/oratab|cut -d: -f1 -s`
export ORACLE_HOME=`grep "$oraSid:" /etc/oratab|cut -d: -f2 -s`
export ORAENV_ASK=NO
#. oraenv ${dbSid}
unset TWO_TASK
export PATH=$PATH:$ORACLE_HOME/bin

#echo $ORACLE_SID
#echo $ORACLE_HOME
#echo $PATH

sqlplus -S " / as sysdba" @/oracle/AWR/create_awr_report_for_database.sql

# Finish
#------------------------------------------------------------------------------

2) create_awr_report_for_database.sql

/* ---------------------------------------------------------------------------
Original script byhttp://damir-vadas.blogspot.in/2009/11/automated-awr-reports-in-oracle-10g11g.html

 Filename: create_awr_report_for_database.sql
 Purpose : In directory defined with v_dir, create awr reports for last one hour snapshots, so put in crontab  to run at every hour on daily basis

 Remarks : Run as privileged user

#  If No report generated in report folder (v_dir) create directory manually once before running the script.
 --------------------------------------------------------------------------- */
set serveroutput on
set linesize 166
set pagesize 600
set trimout on

DECLARE
   CURSOR c_instance
   IS
        SELECT   instance_number, instance_name
          FROM   gv$instance
      ORDER BY   1;

   c_dir CONSTANT   VARCHAR2 (256) := 'oracle/AWR';
   v_dir            VARCHAR2 (256) := 'oracle/AWR/daily_awr';
   v_dbid           v$database.dbid%TYPE;
   v_dbname         v$database.name%TYPE;
   v_inst_num       v$instance.instance_number%TYPE := 1;
   v_begin          NUMBER;
   v_end            NUMBER;
   v_start_date     VARCHAR2 (20);
   v_end_date       VARCHAR2 (20);
   v_options        NUMBER := 8;        -- 0=no options, 8=enable addm feature
   v_file           UTL_FILE.file_type;
   v_file_name      VARCHAR (50);
BEGIN
   -- get database id
   SELECT   dbid, name
     INTO   v_dbid, v_dbname
     FROM   v$database;

   -- get end snapshot id
   SELECT   MAX (snap_id)
     INTO   v_end
     FROM   dba_hist_snapshot
     WHERE  TO_CHAR (END_INTERVAL_TIME, 'yyyy/mm/dd hh24') <= to_char(sysdate,'yyyy/mm/dd hh24');

   DBMS_OUTPUT.put_line ('end snap_id ' || v_end);

   -- get start snapshot id
   SELECT   MAX (snap_id)
     INTO   v_begin
     FROM   dba_hist_snapshot
    WHERE   snap_id < v_end;

   DBMS_OUTPUT.put_line ('begin snap_id ' || v_begin);

   SELECT   TO_CHAR (END_INTERVAL_TIME, 'YYMMDD_HH24MI')
     INTO   v_start_date
     FROM   dba_hist_snapshot
    WHERE   snap_id = v_begin AND instance_number = v_inst_num;

   DBMS_OUTPUT.put_line ('v_start_date ' || v_start_date);

   SELECT   TO_CHAR (END_INTERVAL_TIME, 'HH24MI')
     INTO   v_end_date
     FROM   dba_hist_snapshot
    WHERE   snap_id = v_end AND instance_number = v_inst_num;

   DBMS_OUTPUT.put_line ('v_end_date ' || v_end_date);

   -- Thanx to Yu Denis Sun - we must have directory defined as v_dir value!
execute immediate('create or replace directory awrdir as '''||v_dir||'''');

   -- let's go to real work...write awrs to files...
   FOR v_instance IN c_instance
   LOOP
      DBMS_OUTPUT.put_line (
         'v_instance.instance_name:' || v_instance.instance_name
      );
      v_file :=
         UTL_FILE.fopen (
            'AWRDIR',
               'awr_'
            || v_instance.instance_name
            || '_'
            || v_instance.instance_number
            || '_'
            || v_start_date
            || '_'
            || v_end_date
            || '.html',
            'w',
            32767
         );

      FOR c_report
      IN (SELECT   output
            FROM   TABLE(DBMS_WORKLOAD_REPOSITORY.awr_report_html (
                            v_dbid,
                            v_instance.instance_number,
                            v_begin,
                            v_end,
                            v_options
                         )))
      LOOP
         UTL_FILE.PUT_LINE (v_file, c_report.output);
      END LOOP;

      UTL_FILE.fclose (v_file);
   END LOOP;

EXECUTE IMMEDIATE ('drop directory AWRDIR');
EXCEPTION
   WHEN OTHERS
   THEN
      DBMS_OUTPUT.PUT_LINE (SQLERRM);

      IF UTL_FILE.is_open (v_file)
      THEN
         UTL_FILE.fclose (v_file);
      END IF;

      BEGIN
    EXECUTE IMMEDIATE ('drop directory AWRDIR');
      EXCEPTION
         WHEN OTHERS
         THEN
            NULL;
      END;
END;
/
exit;

  ---------------------------------------------------------------------------

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Restoring an RMAN Backup to Another Node /Clone Database

In certain circumstances, it may be desirable to restore a database from an RMAN backup onto a machine other than the original host. 
For example,Restore and recover data at a given point in time for UAT/Testing, or to duplicate a production instance.
The example assumes:
the target database is on host A
the database is to be restored onto host B
the directory structure of host B is different to host A
the ORACLE_SID will not change for the restored database
a recovery catalog is being used
the backups were carried out to disk (for illustrative purposes, and to disassociate from any media manager specific issues)

The following steps are required:
1. backup the target on host A
2. list the datafile locations on host A
3. make the backup available to host B
4. make a copy of the init.ora available to host B
5. edit the init.ora to reflect directory structure changes
6. configure SQL*Net connectivity from host to the recovery catalog and duplicated database
7. set up a password file for the duplicated database
8. startup nomount the duplicated database
9. RMAN restore the controlfile(s)
10. mount the database
11. restore and rename the datafiles
12. recover and open the database
These steps are expanded further below.

1.Backup the Target on Host A
The target database needs to be backed up using RMAN. The following  commands of RMAN doing an online database backup. In this example, the backup sets are written to disk.

RMAN>
run {
allocate channel t1 type disk;
allocate channel t2 type disk;
allocate channel t3 type disk;
#backup the whole db
backup tag whole_database_open format '/oracle/backups/df_%u' database;
# switch out of the current logfile
sql 'alter system archive log current';
#backup the archived logs
backup archivelog all format '/oracle/backups/al_%u';
# backup a copy of the controlfile that contains records for the other backups just made
backup current controlfile tag = cf1 format '/oracle/backups/cf_%u';
}

2.List Datafile Locations on Host A
The datafile numbers and location on host A are required. These datafile locations will change on host B 
select file#, name from v$datafile;
file#   name
-----   -----------------------------------------------------------
1       /oracle/OFA_base/u01/oradata/TEST/system01.dbf
2       /oracle/OFA_base/u01/oradata/TEST/rbs01.dbf
3       /oracle/OFA_base/u01/oradata/TEST/temp01.dbf
4       /oracle/OFA_base/u01/oradata/TEST/tools01.dbf
5       /oracle/OFA_base/u01/oradata/TEST/users01.dbf
6       /oracle/OFA_base/u01/oradata/TEST/users02.dbf
7       /oracle/OFA_base/u01/oradata/TEST/rbs02.dbf
8       /oracle/OFA_base/u01/oradata/TEST/rcvcat.dbf

The log file names should also be recorded
select group#, member from v$logfile;
group#    member
---------   -----------------------------------------------------------
1            /oracle/OFA_base/u01/oradata/TEST/redo01.log
2            /oracle/OFA_base/u01/oradata/TEST/redo02.log
3            /oracle/OFA_base/u01/oradata/TEST/redo03.log

3 Make the Backups Available to Host B
3.1 Disk Backups
During restore, RMAN will expect the backup sets to be located in the same directory as written to during the backup. For disk backups, the DBA can accomplish this in many ways: set up an NFS directory, mounted on both host A and host B create the same directory structure on host A and host B, use of symbolic links on host B,FTP backup to host B.
If backup directory is not same at HOST B then catalog backup files using RMAN.
3.2 Tape Backups
The media management software must be configured such that host B is a media manager client, and can read the backup sets. The media management vendor should be consulted for support on this issue.

4. and 5. init.ora on host B
The "init.ora" needs to be made available on host B. Any location specific parameters must be ammended. For example,
*_dump_dest
log_archive_dest*
control_files

6. SQL*Net configuration
If running rman from host A:
a. connectivity to the catalog remains unchanged
b. configure tnsnames.ora on host A to connect to duplicated db on host B configure listener.ora on host B to accept connections for duplicated database
If running rman from host B:
a. configure tnsnames.ora on host B to connect to catalog listener.ora on catalog host remains unchanged
b. configure tnsnames.ora on host B to connect to duplicated db on host B configure listener.ora on host B to accept connections for duplicated database
If running rman from host C (ie, neither host A or host B):
a. connectivity to the catalog remains unchanged
b. configure tnsnames.ora on host C to connect to duplicated db on host B configure listener.ora on host B to accept connections for duplicated database

7. Setup Password File
In order to allow RMAN remote connections, a password file must be setup for the duplicated database. 
orapwd file=$ORACLE_HOME/dbs/orapw$ORACLE_SID password=password1

8. Startup nomount the database
SVRMGR> startup nomount pfile=<location of init.ora>

9. RMAN restore the controlfile(s)
Restore the controlfile(s). 
RMAN>
run{
allocate channel c1 type disk;
restore controlfile;
}

10. Mount the database
SVRMGR> alter database mount;

11. Rename and restore the datafiles
Rename and Restore the Files, and perform database recovery. RMAN can be used to change the location of the datafiles from the location on host A (see Section 2) to the new location on host B.
RMAN>
run {
allocate channel c1 type disk;
allocate channel c2 type disk;
allocate channel c3 type disk;
set newname for datafile 1 to '/oracle/datafiles/system01.dbf';
set newname for datafile 2 to '/oracle/datafiles/rbs01.dbf';
set newname for datafile 3 to '/oracle/datafiles/temp01.dbf';
set newname for datafile 4 to '/oracle/datafiles/tools01.dbf';
set newname for datafile 5 to '/oracle/datafiles/users01.dbf';
set newname for datafile 6 to '/oracle/datafiles/users02.dbf';
set newname for datafile 7 to '/oracle/datafiles/rbs02.dbf';
set newname for datafile 8 to '/oracle/datafiles/rcvcat.dbf';
restore database;
switch datafile all;
}


12. Recover and open the database
Perform incomplete recovery:
SVRMGR> recover database using backup controlfile until cancel;
Forward the database applying archived redo log files until you decide to stop recovery by typing cancel at the prompt (assuming that you have required archived redo log files in the log_archive_dest directory). You may archive the source database redo log files and apply them at the target database if required.
SVRMGR> alter database open resetlogs;
Note: this will create the online redo logs in the same location as that on host A. If this directory location does not exist, then this will fail with:
ora344 : unable to recreate online log <name>
The workaround is to rename the logfiles prior to opening the database:
SVRMGR> alter database rename file '<host A location>' to '<host B location>';
Alternatively, the logfile groups can be dropped and recreated. 

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Full Database Recovery or Disaster Recovery.

You use the RESTORE and RECOVER commands to restore and recover the database.RMAN checks last good backup set and restore the datafiles to the state they were in when that backup set was created. When restoring database files with RMAN, it reads the datafile header and makes the determination as to whether the file needs to be restored.
 
If you cannot restore datafiles to their default locations, then you must update the control file to reflect the new locations of the datafiles. Use the RMAN SET NEWNAME command within a RUN command to specify the new filename. Afterward, use a SWITCH command, which is equivalent to using the SQL statement ALTER DATABASE RENAME FILE, to update the names of the datafiles in the control file. SWITCH DATAFILE ALL updates the control file to reflect the new names for all datafiles for which a SET NEWNAME has been issued in a RUN command.(Restore files to another location will  be demonstrated in another post)

The recovery is done by allocating a channel for I/O and then issuing the RMAN restore database command. The database must be in MOUNT state when restoring or recovering the entire database.

SQL> startup mount;
   or
RMAN> startup force mount;

Then connect to rman and perform:
RMAN> restore database;
RMAN> recover database;
RMAN> alter database open;

Another option with controlfile restoration
SET DBID <database_id>; # use database id from RMAN, not required if using recovery catalog
CONNECT TARGET <target_connect_string>;
STARTUP NOMOUNT;
RUN
{
# You need to allocate channels if not using recovery catalog.
ALLOCATE CHANNEL CH1 TYPE DISK;
# Optionally you can use SET NEWNAME and SWITCH commands to restore datafiles to a new location.
RESTORE CONTROLFILE FROM AUTOBACKUP;
ALTER DATABASE MOUNT;
RESTORE DATABASE;
RECOVER DATABASE;
ALTER DATABASE OPEN RESETLOGS;

Another Method: Restore Spfile and Controlfile
1 Assuming that we have a full backup under /bkp
2 Start RMAN
$ rman target / nocatalog
3 Start the DB (nomount) and restore the pfile
RMAN> set DBID=248804095;
startup nomount;
run
{
restore spfile to pfile '/oracle/product/10.2.0/dbs/initTEST.ora'  from'/bkp/c2488040952009013004';
shutdown immediate;
}
4 Start the DB with the pfile that we just restore:
RMAN> set DBID=248804095;
RMAN> startup nomount pfile = '/oracle/product/10.2.0/dbs/initTEST.ora';
5 Restore the control files
run
{
restore controlfile from '/bkp/c2488040952009013004';
alter database mount;
}
6 Restore the data files
run
{
restore database;
recover database;
}
7 Start the DB
RMAN> alter database open resetlogs;

Use RESETLOGS after a point in time recovery  or recover a database using a backup of the control file. RESETLOGS will initialize the logs, reset your log sequence number, and start a new "incarnation" of the database. 

During the recovery, RMAN automatically restores backups of any needed archived redo logs. If  RMAN restores archived redo logs to the flash recovery area during a recovery, then it automatically deletes the restored logs after applying them to the datafiles. Otherwise, you can use the DELETE ARCHIVELOG command to delete restored archived redo logs from disk when they are no longer needed for recovery. For example, you can enter the following command: RECOVER DATABASE DELETE ARCHIVELOG;

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