CLONE ORACLE RAC 10g

Follow these easy steps to clone your existing RAC environment on the same machine hosted on ASM.

In this exercise we duplicate the Two node RAC-instance into a single instance Database and then put that single instace into a two node RAC database

1) Created passwdfile for the AUX_DB instace. This file is at $ORACLE_HOME/dbs
    
2)Updated the parameter file.

Following Two parameter must be included
*.db_file_name_convert='+DATADG/source/','+DATADG/clone/'
*.log_file_name_convert='+DATADG/source/','+DATADG/clone/'
Remove RAC specific paramaters from the parameter file.

3) place the AUXILARY  instance in no-mount mode

Using RMAN restore the backup
$ rman target sys/xxxx@clone;
RMAN> connect AUXILIARY SYS/xxxx
connected to auxiliary database (not started)
RMAN> connect catalog username/password@service_catalogDB
connected to recovery catalog database

RMAN> run {                                                                                                  
2> ALLOCATE CHANNEL disk1 DEVICE TYPE DISK;  
3> ALLOCATE CHANNEL disk2 DEVICE TYPE DISK;  
4> ALLOCATE CHANNEL disk3 DEVICE TYPE DISK;  
5> ALLOCATE CHANNEL disk4 DEVICE TYPE DISK; 
6> ALLOCATE AUXILIARY CHANNEL <ANY_NAME>  DEVICE TYPE DISK;           
7> DUPLICATE TARGET DATABASE TO <CLONE_DB_NAME>                                                                    
8>   LOGFILE                                                                                              
9>   GROUP 1 ('+DATADG/clone/redo01.log') SIZE 512M,                                                     
10>   GROUP 2 ('+DATADG/clone/redo02.log') SIZE 512M,                                                     
11>   GROUP 3 ('+DATADG/clone/redo03.log') SIZE 512M,                                                     
12>   GROUP 4 ('+DATADG/clone/redo04.log') SIZE 512M;                                                     
13> RELEASE CHANNEL disk1;
14> RELEASE CHANNEL disk2;
15> RELEASE CHANNEL disk3;
16> RELEASE CHANNEL disk4;                                                                                  
17> release channel <NAME_GIVEN_IN_LINE_6>;                                                                                
18> }         


4) during Clone you may get the error
RMAN-06136: ORACLE error from auxiliary database: ORA-38856: cannot mark instance UNNAMED_INSTANCE_2 (redo thread 2) as enabled
its solution is to add the following hidden parameter in the parameter file
_no_recovery_through_resetlogs=TRUE
shutdown the instance, and open with RESETLOGS option.

5) Before moving the single instance i had to move it into TWO node RAC instance, so first i moved the controlfile onto ASM ,
so for that open the database in NO-MOUNt mode and using RMAN moved it onto ASM

RMAN> restore controlfile to '+DATADG/clone/controlfile/controlfile.ctl' from '$ORACLE_HOME/dbs/control01.ctl';

6) Now changed the single instance parameter file init.ora with initCLONE1.ora on NODE1 node and initCLONE2.ora on node-2.
 (You can use your existing RAC parameter files as sample)

7) open the database on both the instances.

8) Add it into cluster with following command.

$ srvctl add database -d DB_NAME -o $ORACLE_HOME [Execute From only 1 instance, $ORACLE_HOME should be replaced with Actual Value]
$ srvctl add instance -d DB_NAME -i CLONE1 -n node1 [Execute From only 1 instance]
$ srvctl add instance -d DB_NAME -i CLONE2 -n node2 [Execute From only 1 instance]
===================== NOTE =================
As this clone was created with RAC DATABASE, So while moving it onto the two instance cluster database, i didnt need to add a UNDO tablespace,
but i had to create the redologs.
while starting the instance at node-2 i got the following error
ORA-01618: redo thread 2 is not enabled - cannot mount
so for that i followed the following steps
thread                               integer     1
SQL> select thread#, enabled from v$thread;
   THREAD# ENABLED
---------- --------
         1 PUBLIC
         2 DISABLED

SQL> alter database enable public thread 2;


Users might face multiple issues while performing this process, for example LOG GROUP THREAD 2 will have to be created from instance 1 before starting instance 2. You may post your errors here for me to investigate and give suggestions.