On each node, in the installation owner user profile file, set the environment variables
ORACLE_SID; also add
ORACLE_HOME/bin to the path environment variable.
Set environment variables as shown, in the following example:
export ORACLE_BASE=/u01/app/oracle export ORACLE_HOME=/u01/app/oracle/12.2.0/dbhome_1 export PATH=$PATH:$ORACLE_HOME/bin export ORACLE_SID=sales1
If the environment variables
ORACLE_SID are not set, and you try to use SQL*Plus or other tools, then you receive an error message requesting that you set these variables.