1. Real Application Clusters Installation Guide
  2. Configuring Oracle Homes
  3. Evolution of Oracle Homes
  4. About Read-Only Oracle Homes

About Read-Only Oracle Homes

Starting with Oracle Database 21c, an Oracle Database installation configures all Oracle Database homes in read-only mode by default.

Before Oracle Database 21c, the default ORACLE_HOME layout combined ORACLE_HOME, ORACLE_BASE_HOME and ORACLE_BASE_CONFIG into a single location. Starting with Oracle Database 21c, the only available configuration is a read-only ORACLE_HOME where ORACLE_BASE_HOME and ORACLE_BASE_CONFIG are located separately from ORACLE_HOME.

In a read-only Oracle home, all the configuration data and log files reside outside of the read-only Oracle home. This feature allows you to use the read-only Oracle home as a software image that can be distributed across multiple servers.

Apart from the traditional ORACLE_BASE and ORACLE_HOME directories, the following directories contain files that used to be in ORACLE_HOME:

  • ORACLE_BASE_HOME

  • ORACLE_BASE_CONFIG

Benefits of a Read-Only Oracle Home

  • Enables seamless patching and updating of Oracle Database binaries without extended downtime.

  • Simplifies patching and mass rollout, as only one image needs to be updated to distribute a patch to many servers.

  • Simplifies provisioning by implementing separation of installation and configuration.

Note:

This feature does not affect how database administrators monitor, diagnose, and tune their system performance.

Parent topic: Evolution of Oracle Homes