After you have installed the Oracle Database 12c release 2 (12.2) with Oracle Real Application Clusters (Oracle RAC) software, there are postinstallation tasks to complete.

• Required Postinstallation Tasks
  Perform these tasks after completing your installation.
• Recommended Postinstallation Tasks
  Oracle recommends that you complete these tasks after completing an Oracle RAC installation.
• Product-Specific Postinstallation Tasks
  Many Oracle products and options must be configured before you use them for the first time.
• Configuring the Oracle Home User
  Under certain circumstances you may have to perform additional configuration steps for the Oracle Home user.
• Oracle Configuration Manager Postinstallation Configuration for Oracle RAC
  If you have installed Oracle Configuration Manager, then you must run a script to create a database account to collect database configuration collections.
• Enabling and Disabling Database Options After Installation
  When you install Oracle Database, some options are enabled and the others disabled. You can view the enabled Oracle Database options by querying the V$OPTION view using SQL*Plus.