Rman Duplicate database from Active database

From 11g above, you can use rman to duplicate database from an active database instead of from a backup.
Two big disadvantages of the ACTIVE database duplication method are:

·         Negative performance impact on the source database. This impact applies to the whole duplication time.

·         High network traffic on the connection between the source and target databases.

Test envorinment:

Source

     SID: testprd

     host:192.168.96.3

Target

     SID: testrman

      host: 192.168.96.4

On 192.168.96.4

1.       Create folders:

mkdir -p /orasw/app/oracle/admin/testrman

mkdir -p /orasw/app/oracle/admin/testrman/adump

mkdir -p /orasw/app/oracle/admin/testrman/dpdump

mkdir -p /orasw/app/oracle/admin/testrman/pfile

mkdir -p /11g12c/oradata/testrman

mkdir -p /11g12c/oradata/testrman/arc

mkdir -p /11g12c/redoa/testrman

mkdir -p /11g12c/redob/testrman

2.       Init.ora

Set the following parameters:

*.db_name='testrman'

DB_UNIQUE_NAME=testrman

LOG_ARCHIVE_DEST='/11g12c/oradata/testrman/arc'

LOG_ARCHIVE_DEST_STATE_1=ENABLE

DB_FILE_NAME_CONVERT='testprd','testrman'

LOG_FILE_NAME_CONVERT='testprd','testrman'

3.       ln -s /orasw/app/oracle/admin/testrman/pfile/init.ora $ORACLE_HOME/dbs/inittestrman.ora

4.       orapwd file=/orasw/app/oracle/product/12.1.0/dbs/orapwtestrman password=***** 

5.   Add to the tnsnames.ora on source and destination server.

TESTRMAN =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.96.4)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = TESTRMAN)

      (UR = A)

    )

  )

6.       Listener.ora on destination server

[testrman] /orasw/app/oracle/product/12.1.0/network/admin >cat listener.ora

SID_LIST_LISTENER=

 (SID_LIST=

  (SID_DESC=

   (SID_NAME=testrman

   (GLOBAL_DBNAME=testrman)

  (ORACLE_HOME=/orasw/app/oracle/product/12.1.0/)))

7.       Start testrman with nomount:

[testrman] /orasw/app/oracle/admin/testrman/pfile >sqlplus / as sysdba

SQL*Plus: Release 12.1.0.2.0 Production on Tue Jan 24 15:23:31 2017

Copyright (c) 1982, 2014, Oracle.  All rights reserved.

Connected to an idle instance.

SQL> startup nomount

ORACLE instance started.

Total System Global Area  419430400 bytes

Fixed Size                  2925120 bytes

Variable Size             264244672 bytes

Database Buffers          146800640 bytes

Redo Buffers                5459968 bytes

SQL> quit

8.       Duplicate database:

rman target sys/****@testprd auxiliary sys/****@testrman

run

{

allocate channel c1 type disk;

allocate channel c2 type disk;

allocate channel c3 type disk;

allocate channel c4 type disk;

allocate auxiliary channel a1 type disk;

allocate auxiliary channel a2 type disk;

duplicate target database to testrman from active database;

}