Oracle10g Automated RAC Services Configuration

The Database Configuration Assistant (DBCA) can now be used to fully configure Real Application Clusters (RAC) environments. In order to use this new feature there are certain prerequisites that must be met:

• A shared disk subsystem must in place
• Either RAW filesystems or Oracle Cluster File System (or a compatible CFS provided by your system vendor) must be installed and configured
• Oracle Cluster Ready Services must be installed and configured (this encompasses what were formally Oracle Cluster Manager (oracm) and the global services daemon (GSD). In addition to GSD, the CRS starts the EVMD, CSSD, and CRSD daemons.
• The Oracle Database 10g software must be installed.

Once the above prerequisites are met the DBCA program will recognize that you are running in a clustered environment and will provide you the options of configuring the RAC environment. If the proper services are running, the DBCA will automatically provide the required configuration screens.

The DBCA processing steps are:

1. Depending on the type of storage you have chosen, the DBCA will:
   • If using Automatic Storage Management (ASM), then the DBCA will initialize the ASM subsystem and then start the ASM instance(s)
   • If using CFS (Cluster File Services), then the DBCA will validate the datafile destination to be validly shared across all the nodes that are going to be part of the cluster database
   • If using raw devices, then the DBCA will validate the raw device tablespaces sizes and then validate their access permissions
2. Next, it creates the database
3. It configures the Oracle network services
4. Then, it creates and starts the high availability services
5. Finally, it starts the listeners and database instances and then starts the high availability services