C Converting to Oracle Real Application Clusters from Single-Instance Oracle Databases

This chapter describes the procedures for converting from Oracle Database 11g release 1 (11.1) single-instance databases to Oracle Real Application Clusters (Oracle RAC) databases.

This appendix contains the following topics:

If you are upgrading from Oracle Parallel Server to Oracle RAC, or from an earlier version of Oracle RAC, then use Oracle Database Upgrade Assistant (DBUA).

The procedures in this chapter assume that your original single-instance database and the target Oracle RAC database are using the same release, and running on the same platform.

Note:

You must use clustered ASM instances for Oracle RAC databases.

See Also:

You must comply with the restrictions of the license you have purchased. To understand the restrictions of your license, refer to Oracle Database Licensing Information

C.1 Administrative Issues for Converting Databases to Oracle RAC

Note the following administrative considerations before converting single-instance databases to Oracle RAC:

  • Backup procedures should be available before converting from a single-instance Oracle Database to Oracle RAC.

  • For archiving with Oracle RAC environments, the archive file format requires a thread number.

  • The archived logs from all instances of an Oracle RAC database are required for media recovery. Because of this, if you archive to a file and you do not use a cluster file system, or some other means to provide shared file systems, then you require a method of accessing the archive logs from all nodes on which the cluster database has instances.

  • By default, all database files are migrated to Oracle-Managed Files (OMF). This feature simplifies tablespace creation, ensures datafile location consistency and compliance with OFA rules, and reduces human error with data file management.

C.2 Converting to Oracle RAC with DBCA

You can use Database Configuration Assistant to convert from single-instance Oracle databases to Oracle RAC. DBCA automates the configuration of the control file attributes, creates the undo tablespaces and the redo logs, and makes the initialization parameter file entries for cluster-enabled environments. It also configures Oracle Net Services, Oracle Clusterware resources, and the configuration for Oracle RAC database management for use by Oracle Enterprise Manager or the SRVCTL utility.

Before you use DBCA to convert a single-instance database to an Oracle RAC database, ensure that your system meets the following conditions:

  • It is a supported hardware and operating system software configuration.

  • It has shared storage: either Oracle Cluster File System or ASM is available and accessible from all nodes. On Linux on POWER systems, ensure that GPFS is available and accessible from all nodes.

  • Your applications have no design characteristics that preclude their use with cluster database processing.

If your platform supports a cluster file system, then you can use it for Oracle RAC. You can also convert to Oracle RAC and use a non-shared file system. In either case, Oracle strongly recommends that you use Oracle Universal Installer (OUI) to perform an Oracle Database 11g release 1 (11.1) installation that sets up the Oracle home and inventory in an identical location on each of the selected nodes in your cluster.

This section describes the following scenarios:

C.2.1 Converting Oracle Database 11g Installations to Oracle RAC Using DBCA

To convert from a single-instance Oracle Database that is on a non-cluster computer to Oracle RAC, perform the procedures described in the following sections, and in the order shown:

C.2.1.1 Back Up the Original Single-Instance Database

Use DBCA to create a preconfigured image of your single-instance database by using the following procedure:

  1. Navigate to the bin directory in $ORACLE_HOME, and start DBCA.

  2. At the Welcome page, click Next.

  3. On the Operations page, select Manage Templates, and click Next.

  4. On the Template Management page, select Create a database template and From an existing database (structure as well as data), and click Next.

  5. On the Source Database page, select the database name in the Database instance list, and click Next.

  6. On the Template Properties page, enter a name for your template in the Name field. Oracle recommends that you use the database name.

    By default, the template files are generated in the directory ORACLE_HOME/assistants/dbca/templates If you choose to do so, you can enter a description of the file in the Description field, and change the template file location in the Template data file field.

    When you have completed entries, click Next.

  7. On the Location of Database Related Files page, select Maintain the file locations, so that you can restore the database to the current directory structure, and click Finish.

DBCA generates two files: a database structure file (template_name.dbc), and a database preconfigured image file (template_name.dfb).

C.2.1.2 Complete Oracle Clusterware Installation

Complete Oracle Clusterware installation, as described in Oracle Database Oracle Clusterware Installation Guide for your platform.

C.2.1.3 Validate the Cluster

Validate the cluster configuration using the Cluster Verification Utility.

C.2.1.4 Copy the Preconfigured Database Image

Copy the preconfigured database image. This includes copying the database structure *.dbc file and the database preconfigured image *.dfb file that DBCA created in the previous procedure "Back Up the Original Single-Instance Database" to a temporary location on the node in the cluster from which you plan to run DBCA.

C.2.1.5 Install Oracle Database 11g Software with Oracle RAC

  1. Run OUI to perform an Oracle Database installation with Oracle RAC.

  2. Select Cluster Installation Mode on the Specify Hardware Cluster Installation page of OUI, and select the nodes to include in your Oracle RAC database.

  3. On the OUI Database Configuration Types page, select the Advanced install type.

    After installing the Oracle Database software, OUI runs postinstallation configuration tools, such as Network Configuration Assistant (NETCA), DBCA, and so on.

  4. On the DBCA Template Selection page, use the template that you copied to a temporary location in the "Copy the Preconfigured Database Image" procedure. Use the browse option to select the template location.

  5. If you selected raw storage on the OUI Storage Options page, then on the DBCA File Locations Tab on the Initialization Parameters page, replace the data files, control files, and log files, and so on, with the corresponding raw device files if you have not set up the DBCA_RAW_CONFIG environment variable. You must also replace default database files with raw devices on the Storage page.

  6. After creating the Oracle RAC database, DBCA displays the Password Management page on which you must change the passwords for database privileged users who have SYSDBA and SYSOPER roles. When DBCA exits, the conversion process is complete.

C.2.2 Converting Single Instance on a Cluster to Oracle RAC using DBCA

There are three scenarios in which a single-instance database can exist on a cluster computer:

C.2.2.1 Single Instance on a Cluster Running from a Cluster-Enabled Oracle Home

Perform the following procedures to convert a single-instance database on a cluster running from a cluster-installed (Oracle Database 11g with RAC) Oracle home.

  1. Use DBCA to create a preconfigured image of your single-instance database as described in the section "Back Up the Original Single-Instance Database". To perform the conversion manually, shut down the single-instance database.

  2. To add nodes to your cluster, add and connect these nodes to the cluster as described in Oracle Database Oracle Clusterware Installation Guide for your platform. Ensure that all of these nodes can access the shared storage. Also, extend the Oracle Clusterware home to the new nodes using the procedures for "Extending Clusterware and Oracle Software to New Nodes" as described in Oracle Clusterware Administration and Deployment Guide.

  3. From the existing Oracle home, extend this home to the new nodes using the procedure "Adding Nodes at the Oracle RAC Database Layer" as described in Oracle Clusterware Administration and Deployment Guide.

  4. From one of the newly added nodes, configure the listeners on the additional nodes using NETCA. Choose the same port number and protocol that you used on the existing node. If NETCA displays the existing node in the node list page, then do not select this node, because the listener is already configured on it.

  5. Convert the database using one of the following procedures:

C.2.2.1.1 Automated Conversion Procedure Using DBCA
  1. If you created the preconfigured image of the single instance database as described in the section "Back Up the Original Single-Instance Database", then use DBCA to complete the conversion to an Oracle RAC database.

  2. Start DBCA from the initial node. Select the names of the nodes that you want to include as part of your cluster database. On the Template Selection page, select the preconfigured template that you created in Step 1. Enter the database name and respond to the remaining DBCA prompts.

  3. To use raw devices for the cluster database files: When the Initialization Parameters page appears, enter the raw device name for the SPFILE on the File Locations tab. On the Storage page, replace the default database file names with the raw devices for the control files, redo logs, and data files to create the cluster database. Click Finish, and create the database.

After creating the Oracle RAC database, DBCA displays the Password Management page on which you must change the passwords for the database privileged users who have SYSDBA and SYSOPER roles. When DBCA exits, the conversion process is complete.

C.2.2.1.2 Manual Conversion Procedure Using DBCA

Because you did not use DBCA to create a preconfigured image of your single-instance database in step 1, perform the following steps to complete the conversion:

  1. Create the Optimal Flexible Architecture (OFA) directory structure on each of the nodes that you have added.

    See Also:

    "Directory Structures for Oracle RAC" for more information about OFA
  2. If you are converting single-instance database files on a file system to raw devices, then copy the database data files, control files, redo logs, and server parameter file to their corresponding raw devices using the dd command. Otherwise, continue to the next step.

  3. Re-create the control files by running the CREATE CONTROLFILE SQL statement with the REUSE keyword and specify MAXINSTANCES and MAXLOGFILES, and so on, as needed for your Oracle RAC configuration. The MAXINSTANCES recommended default is 32.

  4. Shut down the database instance.

  5. If your single-instance database was using an SPFILE, then create a temporary PFILE from the SPFILE using the following SQL statement:

    CREATE PFILE='pfile_name' from spfile='spfile_name'
    
  6. Set the CLUSTER_DATABASE parameter to TRUE, set the INSTANCE_NUMBER parameter to a unique value for each instance, using a sid.parameter=value syntax.

    If you optimized memory usage on your single-instance database, then adjust the size of the system global area (SGA) to avoid swapping and paging when you convert to Oracle RAC. you should make this adjustment because Oracle RAC requires about 350 bytes for each buffer to accommodate the Global Cache Service (GCS). For example, if you have 10,000 buffers, then Oracle RAC requires about 350 multiplied by 10,000 bytes more memory. Therefore, adjust the size of the SGA by changing the DB_CACHE_SIZE and DB_nK_CACHE_SIZE parameters accordingly.

  7. Start up the database instance using the PFILE created in step 5.

  8. If your single-instance database was using automatic undo management, then create an undo tablespace for each additional instance using the CREATE UNDO TABLESPACE SQL statement. If you are using raw devices, then ensure that the data file for the undo tablespace is on the raw device.

  9. Create redo threads that have at least two redo logs for each additional instance. If you are using raw devices, then ensure that the redo log files are on raw devices. Enable the new redo threads by using an ALTER DATABASE SQL statement. Then, shut down the database instance.

  10. Copy the Oracle password file from the initial node, or from the node from which you are working, to the corresponding location on the additional nodes on which the cluster database will have an instance. Replace the ORACLE_SID name in each password file appropriately for each additional instance.

  11. Add REMOTE_LISTENER=LISTENER_DB_NAME and sid.LOCAL_LISTENER=LISTENER_SID parameters to the PFILE.

  12. Configure the net service entries for the database and instances, and address entries for the LOCAL_LISTENER for each instance and for the REMOTE_LISTENER in the tnsnames.ora file. When you have done this, copy these to all nodes.

  13. Create the SPFILE from the PFILE using the procedures in the section "Procedures for Migrating to the Server Parameter File". If you are not using a cluster file system, then ensure that the SPFILE is on a raw device.

  14. Create the $ORACLE_HOME/dbs/initsid.ora file that contains the following entry:

    spfile='spfile_path_name'
    

    The variable spfile_path_name is the complete path name of the SPFILE.

  15. On the local node, run catclust.sql. This command creates the dictionary views needed for Oracle RAC databases. For example:

    SQL> start ?/rdbms/admin/catclust.sql
    
  16. Add the configuration for the Oracle RAC database and its instance-to-node mapping using SRVCTL.

  17. Start the Oracle RAC database using SRVCTL.

After starting the database with SRVCTL, your conversion process is complete and, for example, you can run the following SQL statement to see the status of all the instances in your Oracle RAC database:

select * from v$active_instances

C.2.2.2 Single Instance on a Cluster Running from an Oracle RAC-Disabled Oracle Home

You can install a single instance on a cluster running from an Oracle RAC-disabled Oracle home if you performed a one-node cluster (with Oracle RAC) installation, but later disabled the Oracle RAC feature by unlinking it from the oracle binary before creating the single instance database. (However, you can also select the local and non-cluster selection on the Node Selection Page to create a single-instance home on a cluster with Oracle RAC disabled.) Perform the following procedures to convert this type of single-instance database to an Oracle RAC database:

  1. Use DBCA to create a preconfigured image of your single-instance database as described in the section "Back Up the Original Single-Instance Database". To perform the conversion manually, shut down the single-instance database.

  2. Change the directory to the lib subdirectory in the rdbms directory under the Oracle home.

  3. Relink the oracle binary by running the following commands:

    make -f ins_rdbms.mk rac_on
    make -f ins_rdbms.mk ioracle 
    
  4. Continue with step 2.

C.2.2.3 Single Instance on a Cluster Running from a Single-Instance Installed Oracle Home

You can only install a single instance on a cluster running from a single-instance installed Oracle home if you selected the local installation option on the OUI Specify Hardware Cluster Installation page during the single-instance Oracle Database 11g release 1 (11.1) installation.

To convert this type of database to an Oracle RAC database, perform the procedures described in the following sections:

  1. "Back Up the Original Single-Instance Database".

  2. "Complete Oracle Clusterware Installation".

  3. "Validate the Cluster".

  4. "Install Oracle Database 11g Software with Oracle RAC". In this step, make sure that you select a new Oracle home other than the one from which the single-instance database was running.

C.2.3 Converting Single-Instance ASM to Cluster ASM Using DBCA

To use Database Configuration Assistant (DBCA) to convert a single-instance node using ASM to an Oracle RAC node using ASM, complete the following procedure:

  1. Shut down the database instance, the ASM instance, and the listener.

    To enable you to shut down and uninstall CSS, run the following command:

    $ORACLE_HOME/bin/localconfig delete
    

    This command removes the CSS auto-start line from the /etc/inittab file.

  2. Follow the instructions Oracle Clusterware Installation Guide for your platform to configure each node that you want to have as a cluster member.

  3. If any cluster member node has had previous versions of Oracle Clusterware (Cluster Ready Services or Oracle Clusterware) installed, then ensure that you remove the file ocr.loc on any node that has been labeled previously as a cluster node. The file ocr.loc is in /etc/oracle on Linux and UNIX, and /var/opt/oracle on Solaris.

  4. log in as the oracle user, and run DBCA in silent mode to deconfigure ASM. To run DBCA in silent mode, navigate to the directory $ORACLE_HOME/bin and use the following command syntax on the local node:

    dbca -silent -deleteASM
    

    You can de-install the single-instance ASM without losing data.

  5. Install Oracle Clusterware on all nodes you intend to have as cluster members, as described in Oracle Clusterware Installation Guide for your platform.

  6. Install Cluster ASM using DBCA. At the Node Selection page, select all the cluster member nodes for which you intend to use ASM to manage storage. When the ASM Disk Groups page prompts you to select disk groups, select the existing disk groups you used with the single-instance ASM instance that you deleted in step 4.

  7. Start up the single-instance Oracle Database.

C.3 Preparing to Convert with rconfig and Oracle Enterprise Manager

You can use rconfig, or Oracle Enterprise Manager to assist you with the task of converting a single-instance database installation to an Oracle RAC database. The first of these, rconfig, is a command line utility. Oracle Enterprise Manager Grid Control database administration option, Convert to Cluster Database, provides a GUI conversion tool. The following sections describe how to use these conversion tools:

Note:

Before you start the conversion, as is always true before you start any major change to your database, always back up your existing database.

C.3.1 Prerequisites for Converting to Oracle RAC Databases

Before you convert a single-instance database to an Oracle RAC database, ensure that the following conditions are met for each cluster node that you intend to make an Oracle RAC database node:

  • Oracle Clusterware 11g release 1 (11.1) is installed, configured, and running.

  • Oracle RAC 11g release 1 (11.1) software is installed.

  • The Oracle binary is enabled for Oracle RAC.

  • Shared storage, either Oracle Cluster File System or ASM, is available and accessible from all nodes.

  • User equivalence exists for the oracle account.

  • If you intend to use Oracle Enterprise Manager, then all Oracle Enterprise Manager agents are configured and running, and are configured with cluster and host information.

  • You have backed up your existing database.

Note:

You must use clustered ASM instances for Oracle RAC databases. The rconfig utility can migrate single instance ASM storage to clustered ASM storage. If you want to use this option, then you can use the file ConverttoClusteredASM.xml, which is located in the path $ORACLE_HOME/assistants/rconfig/SampleXMLs.

Provide the SID for the ASM instance on the local node in the rconfig XML file. For example:

<!--ASMInfo element is required only if the current non-rac database uses ASM Storage -->
              <n:ASMInfo SID="+ASM">

The ASM instance name you specify in the XML file is only the local ASM instance. Ensure that ASM instances on all the nodes you want to have as cluster members are running, and that the required diskgroups are mounted on each of them.

You can identify the ASM disk groups by issuing the following statement when connected to an ASM instance:

> select name, state, total_mb, free_mb from v$asm_diskgroup

C.3.2 Configuration Changes during Oracle RAC Conversion Using RCONFIG

Note the following changes that occur when you convert a single-instance database to Oracle RAC using rconfig:

  • During the conversion, rconfig places the target Oracle RAC database into archive log mode, and enables archiving for the database. If you do not plan to use archivelog space, then you can disable archive logging after the conversion has completed.

  • For the Shared Storage Type value, if you enter CFS, and you use a cluster file system for your single-instance database storage, then rconfig converts the environment to use Oracle Managed Files (OMF) for database storage, and places the datafiles in a subdirectory located under the shared storage location.

  • During the conversion, rconfig moves database files to a specified shared location, and configures them using OMF.

    If you want to avoid using OMF with your converted database, then the single-instance database files must already be located in a shared file system, and you must indicate that rconfig should not move the files.

C.3.3 Converting Databases to Oracle RAC Using RCONFIG or Oracle Enterprise Manager

The following is a list of scenarios for converting a single-instance Oracle database to an Oracle RAC database:

  • Converting a single-instance Oracle Database 11g release 1 (11.1) to an Oracle 11g release 1 (11.1) Oracle RAC database, running out of the same Oracle home and using the same data files as the single-instance database.

    In this scenario, either use the rconfig utility, or use the Convert to RAC option on the single-instance database target of Oracle Enterprise Manager Grid Control.

  • Converting a single-instance Oracle Database version previous to Oracle Database 11g release 1 (11.1), running out of the same Oracle home and using the same data files as the single-instance database

    In this scenario, use OUI and Database Upgrade Assistant (DBUA) to update the single-instance database to Oracle Database 11g release 1 (11.1). Then use rconfig or the Oracle Enterprise Manager Convert to RAC option, as described in the preceding scenario.

  • Converting a single-instance Oracle Database 11g release 1 (11.1) to an Oracle 11g release 1 (11.1) Oracle RAC database, running out of a different Oracle home and using the same data files as the single-instance database.

    In this scenario, either use the rconfig utility in the target database home, or use the Convert to RAC option in the single-instance database target of Oracle Enterprise Manager Grid Control. Provide the file storage location when prompted.

  • Converting a single-instance Oracle Database 11g release 1 (11.1) to an 11g release 1 (11.1) Oracle RAC database, running out of a different Oracle home, and where the host where the single-instance database is running is not one of the nodes of the Oracle RAC database.

    In this scenario, create a clone image of the single-instance database, and move the clone image to a host that is one of the nodes of the cluster. Then use rconfig or the Oracle Enterprise Manager Convert to RAC option, as described in the preceding scenario.

C.3.4 Converting Databases to Oracle RAC Using Oracle Enterprise Manager

You can use Oracle Enterprise Manager Grid Control to convert a single-instance database to Oracle RAC. To use this feature, complete the following steps:

See Also:

Oracle Database Upgrade Guide for information about upgrading existing Oracle Database installations
  1. Log in to Grid Control. From the Grid Control Home page, click the Targets tab.

  2. On the Targets page, click the Databases secondary tab, and click the link in the Names column of the database that you want to convert to Oracle RAC.

  3. On the Database Instance Home page, click the Change Database secondary tab.

  4. On the Administration page, in the Database Administration Change Database section, click Convert to Cluster Database.

  5. Log in as the database user SYS with SYSDBA privileges to the database you want to convert, and click Next.

  6. On the Convert to Cluster Database: Cluster Credentials page, provide a user name and password for the oracle user and password of the target database that you want to convert. If the target database is using ASM, then also provide the ASM SYS user and password, and click Next.

  7. On the Hosts screen, select the host nodes in the cluster that you want to be cluster members in the Oracle RAC database installed. When you have completed your selection, click Next.

  8. On the Convert to Database: Options page, select whether you want to use the existing listener and port number, or specify a new listener and port number for the cluster. Also provide a prefix for cluster database instances on the cluster.

    When you have finished entering information, click Next, or click Help if you need assistance in deciding how to enter information.

  9. On the Convert to Cluster Database: Shared Storage page, either select the option to use your existing shared storage area, or select the option to have your database files copied to a new shared storage location. Also, decide if you want to use your existing Fast Recovery area, or if you want to copy your Fast Recovery files to a new Fast Recovery area using files managed by Oracle Database.

    If you use ASM, then Oracle recommends that you place the database area and the recovery area in separate failure groups. A failure group is defined by shared hardware, such as a controller shared between two disks, or two disks that are on the same spindle. If two disks share hardware that could fail, making both disks unavailable, then theses disks are said to be in the same failure group. If you do not use ASM, then Oracle recommends that the data files and the Fast Recovery area are located on separate locations, as with separate ASM failure groups, so that a hardware failure does not affect availability.

    When you have finished entering information, click Next, or click Help if you need assistance in deciding how to enter information.

  10. On the Convert to Cluster Database: Review page, review the options you have selected. Click Submit Job if you want to proceed to conversion. If you want to change options you have selected, click Back. To cancel the conversion, click Cancel.

  11. On the Confirmation page, click View Job to check the status of the conversion.

C.4 Converting Databases to Oracle RAC Using RCONFIG

You can use the command line utility rconfig to convert a single-instance database to Oracle RAC. To use this feature, complete the following steps:

Note:

If the single-instance database is using ASM storage, then use rconfig to convert the database in the following order:
  1. Convert the single-instance ASM configuration to clustered ASM, substituting the file ConverttoClusteredASM.xml as the input XML file for rconfig. The ConverttoClusteredASM.xml file is located in the path $ORACLE_HOME/assistants/rconfig/SampleXMLs.

  2. Convert the single-instance database using the following procedure.

If the single-instance database is already using clustered ASM, then proceed directly to conversion of the single-instance database.

See Also:

Oracle Database Upgrade Guide for information about upgrading existing Oracle Database installations
  1. As the oracle user, navigate to the directory $ORACLE_HOME/assistants/rconfig/sampleXMLs, and open the file ConvertToRAC.xml using a text editor, such as vi.

  2. Review the ConvertToRAC.xml file, and modify the parameters as required for your system. The XML sample file contains comment lines that provide instructions for how to configure the file.

    Caution:

    Set the convert option Convert verify="ONLY" to perform a test conversion to ensure that a conversion can be completed successfully.

    When you have completed making changes, save the file with the syntax filename.xml. Make a note of the name you select.

  3. Navigate to the directory $ORACLE_HOME/bin, and use the following syntax to run the command rconfig:

    rconfig input.xml
    

    where input.xml is the name of the XML input file you configured in step 2.

    For example, if you create an input XML file called convert.xml, then enter the following command

    $ ./rconfig convert.xml
    

Note:

The Convert verify option in the ConvertToRAC.xml file has three options:
  • Convert verify="YES": rconfig performs checks to ensure that the prerequisites for single-instance to Oracle RAC conversion have been met before it starts conversion

  • Convert verify="NO": rconfig does not perform prerequisite checks, and starts conversion

  • Convert verify="ONLY" rconfig only performs prerequisite checks; it does not start conversion after completing prerequisite checks

If performing the conversion fails, then use the following procedure to recover and reattempt the conversion.:

  1. Attempt to delete the database using the DBCA delete database option.

  2. Restore the source database.

  3. Review the conversion log, and fix any problems it reports that may have caused the conversion failure. The rconfig log files are under the rconfig directory in $ORACLE_BASE/cfgtoollogs.

  4. Reattempt the conversion.

C.5 Example of an rconfig XML Input File for ConvertToRAC

The following is an example of an XML ConvertToRAC input file for the rconfig utility. In the example, the XML input file is for converting a single-instance database with ASM to an Oracle RAC database with ASM in the same Oracle home.

<?xml version="1.0" encoding="UTF-8"?>
<n:RConfig xmlns:n="http://www.oracle.com/rconfig/"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://www.oracle.com/rconfig/">
    <n:ConvertToRAC>   
<!-- Verify does a precheck to ensure all pre-requisites are met, before the conversion is attempted. Allowable values are: YES|NO|ONLY -->
        <n:Convert verify="YES">
<!--Specify current OracleHome of non-rac database for SourceDBHome -->
              <n:SourceDBHome>C:/oracle/rac11home</n:SourceDBHome>
<!--Specify OracleHome where the rac database should be configured. It can be same as SourceDBHome -->
              <n:TargetDBHome>C:/oracle/rac11home</n:TargetDBHome>
<!--Specify SID of non-rac database and credential. User with sysdba role is required to perform conversion -->
              <n:SourceDBInfo SID="sidb">
                <n:Credentials>
                  <n:User>sys</n:User>
                  <n:Password>oracle</n:Password>
                  <n:Role>sysdba</n:Role>
                </n:Credentials>
              </n:SourceDBInfo>
<!--ASMInfo element is required only if the current non-rac database uses ASM Storage -->
              <n:ASMInfo SID="+ASM1">
                <n:Credentials>
                  <n:User>sys</n:User> 
                  <n:Password>welcome</n:Password>
                  <n:Role>sysdba</n:Role> 
                </n:Credentials>
              </n:ASMInfo>     
<!--Specify the list of nodes that should have rac instances running. LocalNode should be the first node in this nodelist. -->
              <n:NodeList>        
                <n:Node name="node1"/>
                <n:Node name="node2"/>
              </n:NodeList>
<!--Specify prefix for rac instances. It can be same as the instance name for non-rac database or different. The instance number will be attached to this prefix. -->
              <n:InstancePrefix>sales</n:InstancePrefix>
<!--Specify port for the listener to be configured for rac database.If port="", alistener existing on localhost will be used for rac database.The listener will be extended to all nodes in the nodelist -->
              <n:Listener port="1521"/>
<!--Specify the type of storage to be used by rac database. Allowable values are CFS|ASM. The non-rac database should have same storage type. -->
              <n:SharedStorage type="CFS">
<!--Specify Database Area Location to be configured for rac database.If this field is left empty, current storage will be used for rac database. For CFS, this field will have directory path. -->
                <n:TargetDatabaseArea>M:\oradata</n:TargetDatabaseArea>
<!--Specify Fast Recovery Area to be configured for rac database. If this field is left empty, current recovery area of non-rac database will be configured for rac database. If current database is not using recovery Area, the resulting rac database will not have a recovery area. -->
                <n:TargetFastRecoveryArea>M:\Fast_sidb</n:TargetFastRecoveryArea>
              </n:SharedStorage>
        </n:Convert>
    </n:ConvertToRAC>
</n:RConfig>

C.6 Converting Single-Instance ASM to Oracle RAC Using RCONFIG

You can use the command line utility rconfig to convert Automatic Storage Management (ASM) configured for a single-instance database to ASM configured fro Oracle RAC. To use this feature, complete the following steps:

See Also:

Oracle Database Upgrade Guide for information about upgrading existing ASM installations
  1. As the oracle user, navigate to the directory $ORACLE_HOME/assistants/rconfig/sampleXMLs, and open the file ConvertToASM.xml using a text editor, such as vi.

  2. Review the ConvertToASM.xml file, and modify the parameters as required for your system. The XML sample file contains comment lines that provide instructions for how to configure the file.

    Caution:

    Set the convert option Convert verify="ONLY" to perform a test conversion to ensure that a conversion can be completed successfully.

    When you have completed making changes, save the file with the syntax filename.xml. Make a note of the name you select.

  3. Navigate to the directory $ORACLE_HOME/bin, and use the following syntax to run the command rconfig:

    rconfig input.xml
    

    where input.xml is the name of the XML input file you configured in step 2.

    For example, if you create an input XML file called convert.xml, then enter the following command

    $ ./rconfig convert.xml
    

Note:

The Convert verify option in the ConvertToRAC.xml file has three options:
  • Convert verify="YES": rconfig performs checks to ensure that the prerequisites for single-instance to Oracle RAC conversion have been met before it starts conversion

  • Convert verify="NO": rconfig does not perform prerequisite checks, and starts conversion

  • Convert verify="ONLY" rconfig only performs prerequisite checks; it does not start conversion after completing prerequisite checks

If performing the conversion fails, then use the following procedure to recover and reattempt the conversion.:

  1. Attempt to delete the ASM instance using the DBCA delete ASM option.

  2. Restore the source ASM instance.

  3. Review the conversion log, and fix any problems it reports that may have caused the conversion failure. The rconfig log files are under the rconfig directory in $ORACLE_BASE/cfgtoollogs.

  4. Reattempt the conversion.

C.7 Example of an rconfig XML Input File for ConvertToASM

The following is an example of an XML ConvertToRAC input file for the rconfig utility. This file is available for use in the following path:

$ORACLE_HOME/assistants/rconfig/sampleXMLs 

In this example, the XML input file is for converting a single-instance database with ASM to an Oracle RAC database with ASM in the same Oracle home.

<?xml version="1.0" encoding="UTF-8"?>
<n:RConfig xmlns:n="http://www.oracle.com/rconfig/"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://www.oracle.com/rconfig/rconfig.xsd">
                                                                           
    <n:ConvertToClusteredASM>
                <!-- Verify does a precheck to ensure all pre-requisites are met, before the conversion is attempted. Allowable values are: YES|NO|ONLY -->
        <n:ConvertASM verify="YES">
                <!--Specify current OracleHome of single instance ASM for SourceASMHome -->
              <n:SourceASMHome>/oracle/product/11.1.0/db_1</n:SourceASMHome>
                <!--Specify OracleHome where the clustered ASM should be configured. It can be same as SourceASMHome -->
              <n:TargetASMHome>/oracle/product/11.1.0/db_1</n:TargetASMHome>
                <!--Specify single instance ASM credentials -->
              <n:ASMInfo SID="+ASM">
                <n:Credentials>
                  <n:User>sys</n:User>
                  <n:Password>welcome</n:Password>
                  <n:Role>sysdba</n:Role>
                </n:Credentials>
              </n:ASMInfo>
                <!--Specify the list of nodes that should have clustered ASM instances running. LocalNode should be the first node in this nodelist. -->
              <n:NodeList>
                <n:Node name="node1"/>
                <n:Node name="node2"/>
              </n:NodeList>
                <!--Specify port for the listener to be configured for clustered ASM. If port="", listener existing on localhost will be used for clustered ASM. The listener will be extended to all nodes in the nodelist -->
              <n:Listener port=""/>
                <!--Specify comma-seperated path of ASM diskstring to discover diskgroups that will be mounted on clustered ASM instances. If this path is not accessible from a node in the nodelist, the diskgroup will not be mounted on that node. -->
              <n:ASMDiskString>/dev/raw1/*,/dev/raw2/*</n:ASMDiskString>
        </n:ConvertASM>
    </n:ConvertToClusteredASM>
</n:RConfig>

C.8 Post-Conversion Steps

After completing the conversion, note the following recommendations for Oracle RAC environments, as described in the Oracle RAC documentation:

  • Follow the recommendations for using load balancing and transparent application failover, as described in Oracle Real Application Clusters Administration and Deployment Guide

  • Use locally managed tablespaces instead of dictionary managed tablespaces to reduce contention and manage sequences in Oracle RAC as described in Oracle Real Application Clusters Administration and Deployment Guide

  • Follow the guidelines for using automatic segment space management as described in Oracle Real Application Clusters Administration and Deployment Guide

The buffer cache and shared pool capacity requirements in Oracle RAC are slightly greater than the requirements for single-instance Oracle databases. Therefore, you should increase the size of the buffer cache by about 10%, and the size of the shared pool by about 15%.