Oracle Database startup problems with lsnrctl and EM Express
I have installed Oracle Database Std Edition 12.C/12.1on Oracle Linux 6.x. The install was done as a non-root user ("oracle.") The installer could not create the /etc/oratab file but otherwise looked OK. It did not create a init script to auto start the Oracle DB service on system reboot. It did add the oracle user to the oracle "dba" group in /etc/groups.
tnsping is able to resolve the servername
I updated the /etc/profile file with
JAVA_HOME=/usr/java/latest/
export JAVA_HOME
ORACLE_HOME=/opt/oracle/app/oracle/product/12.1.0/dbhome_1
ORACLE_HOME_LISTNER=/opt/oracle/app/oracle/product/12.1.0/dbhome_1