Optimal Flexible Architecture and the Upgrade Install Oracle Database Tips by Donald Burleson

With a working Oracle 9i RAC installation completed, the next step is to install the software for Oracle 10g release 1. It is important that the directories used for the install comply with the Optimal Flexible Architecture (OFA).

A problem arises with OFA in that the parent directories for the new clustering software, Cluster Ready Services(CRS), must be owned by root, and only root can have write access to those directories. In order to accomplish that task, the clustering software must be installed outside of the $ORACLE_BASE directory. 

Figure 8.1 demonstrates the new $ORACLE_HOME for 10g and the $ORA_CRS_HOME for Cluster Ready Services, with root ownership of the parent directories.

Although the name chosen for the home directory is a matter of personal preference, for this install, the home directory for CRSill be called crs instead of crs_1 because crs_1 could be misinterpreted to mean that more than one install of CRS is possible, which it is not. 

Many database administrators will be happy to learn that 10g install software does not require directories to be pre-created.

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