Cloning is the process of copying an existing Oracle RAC installation to a different location and updating the copied bits to work in the new environment. The changes made by one-off patches applied on the source Oracle home, would also be present after the clone operation. The source and the destination path (host to be cloned) need not be the same.

Some situations in which cloning is useful are:

• Cloning provides a way to prepare an Oracle home once and deploy it to many hosts simultaneously. You can complete the installation silently, as a noninteractive process. You do not need to use a graphical user interface (GUI) console and you can perform cloning from a Secure Shell (SSH) terminal session, if required.

• Cloning enables you to create an installation (copy of a production, test, or development installation) with all patches applied to it in a single step. Once you have performed the base installation and applied all patch sets and patches on the source system, the clone performs all of these individual steps as a single procedure. This is in contrast to going through the installation process to perform the separate steps to install, configure, and patch the installation on each node in the cluster.

• Installing Oracle RAC by cloning is a very quick process. For example, cloning an Oracle home to a new cluster of more than two nodes requires a few minutes to install the Oracle base software, plus a few minutes more for each node (approximately the amount of time it takes to run the root.sh script).

The cloned installation behaves the same as the source installation. For example, the cloned Oracle home can be removed using Oracle Universal Installer or patched using OPatch. You can also use the cloned Oracle home as the source for another cloning operation. You can create a cloned copy of a test, development, or production installation by using the command-line cloning scripts. The default cloning procedure is adequate for most usage cases. However, you can also customize various aspects of cloning, for example, to specify custom port assignments, or to preserve custom settings.

The cloning process works by copying all of the files from the source Oracle home to the destination Oracle home. Thus, any files used by the source instance that are located outside the source Oracle home's directory structure are not copied to the destination location.

The size of the binaries at the source and the destination may differ because these are relinked as part of the clone operation and the operating system patch levels may also differ between these two locations. Additionally, the number of files in the cloned home would increase because several files copied from the source, specifically those being instantiated, are backed up as part of the clone operation.

Use this overview to understand the procedures you use to clone Oracle RAC.

In the preparation phase, you create a copy of an Oracle home that you then use to perform the cloning procedure on one or more nodes. You also install Oracle Clusterware.

# cd /opt/oracle/product/12c/db_1
# tar –zcvf /pathname/db1120.tgz .

After you complete the prerequisite tasks described in "Preparing to Clone Oracle RAC", you can deploy cloned Oracle homes.

Deploy the Oracle RAC database home to a cluster, as follows:

1. Perform any Oracle RAC preinstallation tasks, as described in your platform-specific Oracle RAC installation guide, to prepare the new cluster nodes, such things as:

   • Specify the kernel parameters.

   • Ensure Oracle Clusterware is active.

   • Ensure that Oracle ASM is active and that at least one Oracle ASM disk group exists and is mounted.

2. Deploy the Oracle RAC database software, as follows:

   1. Copy the clone of the Oracle home to all nodes. For example:

      [root@node1 root]# mkdir -p /opt/oracle/product/12c/db
      [root@node1 root]# cd /opt/oracle/product/12c/db
      [root@node1 db]# tar –zxvf /path_name/db1120.tgz

      When providing the home location and path_name, the home location can be in the same directory path or in a different directory path from the source home that you used to create the tar.

   2. If either the oracle user or the oinstall group, or both is different between the source and destination nodes, then change the ownership of the Oracle Inventory files, as follows:

      [root@node1]# chown -R oracle:oinstall /opt/oracle/product/12c/db

      When you run the preceding command on the Oracle RAC home, it clears setuid and setgid information from the Oracle binary.

      Note:

      You can perform this step at the same time you perform Step 3 and Step 4 to run the clone.pl and $ORACLE_HOME/root.sh scripts on each cluster node.

3. Run the clone.pl script on each node, which performs the main Oracle RAC cloning tasks, as follows:

   1. Supply the environment variables and cloning parameters in the start.sh script, as described in Table 9-2 and Table 9-3. Because the clone.pl script is sensitive to the parameters being passed to it, you must be accurate in your use of brackets, single quotation marks, and double quotation marks.

   2. Run the script as oracle or the user that owns the Oracle RAC software.

   The following table lists and describes the clone.pl script parameters:

   Table 9-1 clone.pl Script Parameters

   Parameter	Description
   ORACLE_HOME=Oracle_home	The complete path to the Oracle home you want to clone. If you specify an invalid path, then the script exits. This parameter is required.
   ORACLE_BASE=ORACLE_BASE	The complete path to the Oracle base you want to clone. If you specify an invalid path, then the script exits. This parameter is required.
   ORACLE_HOME_NAME= Oracle_home_name | -defaultHomeName	The Oracle home name of the home you want to clone. Optionally, you can specify the -defaultHomeName flag. This parameter is optional.
   ORACLE_HOME_USER=Oracle_home_user	The OracleHomeUser for Windows services. This parameter is applicable to Windows only and is optional.
   OSDBA_GROUP=group_name	Specify the operating system group you want to use as the OSDBA privileged group. This parameter is optional.
   OSOPER_GROUP=group_name	Specify the operating system group you want to use as the OSOPER privileged group. This parameter is optional.
   OSASM_GROUP=group_name	Specify the operating system group you want to use as the OSASM privileged group. This parameter is optional.
   OSBACKUPDBA_GROUP=group_name	Specify the operating system group you want to use as the OSBACKUPDBA privileged group. This parameter is optional.
   OSDGDBA_GROUP=group_name	Specify the operating system group you want to use as the OSDGDBA privileged group. This parameter is optional.
   OSKMDBA_GROUP=group_name	Specify the operating system group you want to use as the OSKMDBA privileged group. This parameter is optional.
   -debug	Specify this option to run the clone.pl script in debug mode
   -help	Specify this option to obtain help for the clone.pl script.

   The following example shows an excerpt from the start.sh script that calls the clone.pl script:

   ORACLE_BASE=/opt/oracle
   ORACLE_HOME=/opt/oracle/product/12c/db
   cd $ORACLE_HOME/clone
   THISNODE='host_name'
   
   E01=ORACLE_HOME=/opt/oracle/product/12c/db
   E02=ORACLE_HOME_NAME=OraDBRAC
   E03=ORACLE_BASE=/opt/oracle
   C01="-O CLUSTER_NODES={node1,node2}"
   C02="-O LOCAL_NODE=$THISNODE"
   
   perl $ORACLE_HOME/clone/bin/clone.pl $E01 $E02 $E03 $C01 $C02

   The following table lists and describes the environment variables E01, E02, and E03 that are shown in bold typeface in the preceding example:

   Table 9-2 Environment Variables Passed to the clone.pl Script

   Symbol	Variable	Description
   E01	ORACLE_HOME	The location of the Oracle RAC database home. This directory location must exist and must be owned by the Oracle operating system group: oinstall.
   E02	ORACLE_HOME_NAME	The name of the Oracle home for the Oracle RAC database. This is stored in the Oracle Inventory.
   E03	ORACLE_BASE	The location of the Oracle Base directory.

   The following table lists and describes the cloning parameters C01 and C02, that are shown in bold typeface in the preceding example:

   Table 9-3 Cloning Parameters Passed to the clone.pl Script.

   Variable	Name	Parameter	Description
   C01	Cluster Nodes	CLUSTER_NODES	Lists the nodes in the cluster.
   C02	Local Node	LOCAL_NODE	The name of the local node.

   The following example shows an excerpt from the start.bat script that the user must create that calls the clone.pl script:

   set ORACLE_home=C:\oracle\product\12c\db1
   cd %ORACLE_home%\clone\bin
   set THISNODE=%hostname%
   set E01=ORACLE_HOME=%ORACLE_home%
   set E02=ORACLE_HOME_NAME=OraDBRAC
   set E03=ORACLE_BASE=Oracle_Base
   set C01="CLUSTER_NODES={node1,node2}"
   set C02="-O LOCAL_NODE=%THISNODE%"
   perl clone.pl %E01% %E02% %E03% %C01% %C02%

4. Note:

   This step applies to Linux and UNIX installations, only.

   Run the $ORACLE_HOME/root.sh as the root operating system user as soon as the clone.pl procedure completes on the node.

   [root@node1 root]# /opt/oracle/product/12c/db/root.sh -silent

   Note that you can run the script on each node simultaneously:

   [root@node2 root]# /opt/oracle/product/12c/db/root.sh -silent

   Ensure the script has completed on each node before proceeding to the next step.

5. Note:

   You need only run DBCA on one node in the cluster to create Oracle RAC instances on all nodes.

   This step shows how to run DBCA in silent mode and provide response file input to create the Oracle RAC instances.

   The following example creates an Oracle RAC database named ERI on each node, creates database instances on each node, registers the instances in OCR, creates the database files in the Oracle ASM disk group called DATA, and creates sample schemas. It also sets the SYS, SYSTEM, SYSMAN and DBSNMP passwords to password, which is the password for each account:

   [oracle@node1 oracle]$ export ORACLE_HOME=/opt/oracle/product/12c/db
   [oracle@node1 oracle]$ cd $ORACLE_HOME/bin/
   [oracle@node1 bin]$./dbca -silent -createDatabase -templateName General_Purpose.dbc \
   -gdbName ERI -sid ERI \
   -sysPassword password -systemPassword password \
   -sysmanPassword password -dbsnmpPassword password \
   -emConfiguration LOCAL \
   -storageType ASM -diskGroupName DATA \
   -datafileJarLocation $ORACLE_HOME/assistants/dbca/templates \
   -nodelist node1,node2 -characterset WE8ISO8859P1 \
   -obfuscatedPasswords false -sampleSchema true

The cloning script runs multiple tools, each of which may generate its own log files.

After the clone.pl script finishes running, you can view log files to obtain more information about the cloning process.

The following log files that are generated during cloning are the key log files of interest for diagnostic purposes:

• Central_Inventory/logs/cloneActionstimestamp.log

  Contains a detailed log of the actions that occur during the Oracle Universal Installer part of the cloning.

• Central_Inventory/logs/oraInstalltimestamp.err

  Contains information about errors that occur when Oracle Universal Installer is running.

• Central_Inventory/logs/oraInstalltimestamp.out

  Contains other miscellaneous messages generated by Oracle Universal Installer.

• $ORACLE_HOME/clone/logs/clonetimestamp.log

  Contains a detailed log of the actions that occur before cloning and during the cloning operations.

• $ORACLE_HOME/clone/logs/errortimestamp.log

  Contains information about errors that occur before cloning and during cloning operations.

Table 9-4 describes how to find the location of the Oracle inventory directory.