8
Adding Instances and Nodes

This chapter describes how to convert from a single instance Oracle8i database to a multi-instance Oracle8i database using the Oracle Parallel Server Option, and how to add a additional node to an existing xx-node configuration.

Specific topics discussed are:

• Moving from a Single Instance to Parallel Server

• Adding Additional Nodes to a Cluster

Moving from a Single Instance to Parallel Server

This section explains how to migrate from a single instance Oracle8i database to multi-instance. In addition, it can help you extend an existing Oracle Parallel Server configuration to additional nodes.

The steps to migrate from a single instance to an Oracle Parallel Server include:

Step 1: Configure Hardware

Step 2: Evaluate Tablespaces and Log Files of Single Instance

Step 3: Create Raw Devices

Step 4: Export Data from Old Database

Step 5: Install Operating System Dependent Files

Step 6: Install Oracle8i Enterprise Edition and Oracle8i Parallel Server Option

Step 7: Create the Database

Step 8: Transfer Data From Old Data to Empty Database

Step 9: Start the Database

This section should be used as a supplement to Chapter 23, "Migrating from Single Instance to Parallel Server," of the Oracle8i Parallel Server Concepts and Administration. guide.

Step 1: Configure Hardware

See your vendor documentation for information about setting up Oracle Parallel Server hardware.

Step 2: Evaluate Tablespaces and Log Files of Single Instance

Because tablespaces must be identical on the Oracle Parallel Server as a single instance database, it is important that you do any consolidation, addition of, or renaming of tablespaces on the single instance at this time.

Each additional node in the cluster requires two log files. Typically, a single instance database only has two log files. You must add additional log files for each node using the ALTER DATABASE ADD LOGFILE statement.

Step 3: Create Raw Devices

Create the raw devices that will be needed for the data files, control files and log files needed for Oracle Parallel Server, as explained in "Setting Up Raw Devices".

Step 4: Export Data from Old Database

Export the entire database from the single instance database. Use a tool such as the Export utility

To use the Export utility to export all data from an existing database to the new database:

Note: To export an entire database, you must use the user name SYSTEM. Do not use INTERNAL or SYS.

Run the Export utility:

exp username/password file=file.dmp full=y log file.log
     


         

FILE.DMP represents the data from the full database export of the database, while FILE.LOG represents the log of the operation.

See Oracle8i Utilities for further information about this tool.

Step 5: Install Operating System Dependent Files

For all nodes, see your Operating System Dependent vendor documentation for instructions about installing Operating System Dependent files.

Step 6: Install Oracle8i Enterprise Edition and Oracle8i Parallel Server Option

Except on the server already running Oracle8i Enterprise Edition, install Oracle8i Enterprise Edition along with the Oracle Parallel Server option, as described in Chapter 3, "Installation". If your current single instance database does not have the supporting hardware, you must perform a clean install on new cluster hardware.

On the server already running Oracle8i Enterprise Edition, install the Oracle Parallel Server option using the Custom installation type.

Step 7: Create the Database

A new database must be created on the raw partitions. Depending on the install type and subsequent confutation options, a database may be created with the following methods:

• If you selected the Typical install type, the database will be created after installation.

• If you requested the Oracle Database Configuration Assistant run after the Custom install type, the Oracle Database Configuration creates a database.

• If you requested the Oracle Database Configuration Assistant not run after during Custom install type, you can still run the Oracle Database Configuration to create a database. See "Creating the Database".

• If you requested the Oracle Database Configuration Assistant not run after during Custom install type, you can create the database manually.

Step 8: Transfer Data From Old Data to Empty Database

Import the entire database into the empty database. Use a tool such as the Import utility.

To run the Import utility:

imp system/password file=file.dmp full=y log file.log
     


         

FILE.DMP represents the data from the full database export of the database, while FILE.LOG represents the log of the operation.

See Oracle8i Utilities for further information about this tool.

ATTENTION: If the original database from which the export file was generated contains tablespaces that are not in the new database, then the Import utility attempts to create those tablespaces with associated data files. The easy solution is to ensure both databases contain the same tablespaces. The data files do not have to be identical. Only the tablespace names need to be the same.

Step 9: Start the Database

See "Starting the Database in Parallel Mode" to start the Oracle Parallel Server.

Adding Additional Nodes to a Cluster

If you have already configured a xx-node cluster and want to add other nodes, Oracle Corporation recommends the follow procedure:

1. Install another database into a different Oracle home that includes all the nodes you want the to support, as described in Chapter 3, "Installation".

2. Use the Oracle Database Configuration Assistant to configure the database for all the nodes, as described in Chapter 3, "Installation" and "Creating the Database".

3. Export the data from the existing database, as described in "Step 4: Export Data from Old Database".

4. Import the data to the new database, s described in "Step 8: Transfer Data From Old Data to Empty Database".

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