Linux and Oracle Solaris /etc/rc.d/init.d 
# chgrp dba dbora
# chmod 750 dbora


# ln -s /etc/rc.d/init.d/dbora /etc/rc.d/rc0.d/K01dbora
# ln -s /etc/rc.d/init.d/dbora /etc/rc.d/rc3.d/S99dbora
# ln -s /etc/rc.d/init.d/dbora /etc/rc.d/rc5.d/S99dbora



[oracle@VA1CSPPVMDEMO01 etc]$ echo $ORACLE_HOME
/oracle/app/oracle/product/12.2.0/dbhome_1
[oracle@VA1CSPPVMDEMO01 etc]$ echo $ORACLE_SID
ORCL122
[oracle@VA1CSPPVMDEMO01 etc]$ cat oratab
#
# This file is used by ORACLE utilities.  It is created by root.sh
# and updated by either Database Configuration Assistant while creating
# a database or ASM Configuration Assistant while creating ASM instance.

# A colon, ':', is used as the field terminator.  A new line terminates
# the entry.  Lines beginning with a pound sign, '#', are comments.
#
# Entries are of the form:
#   $ORACLE_SID:$ORACLE_HOME:<N|Y>:
#
# The first and second fields are the system identifier and home
# directory of the database respectively.  The third field indicates
# to the dbstart utility that the database should , "Y", or should not,
# "N", be brought up at system boot time.
#
# Multiple entries with the same $ORACLE_SID are not allowed.
#
#
ORCL122:/oracle/app/oracle/product/12.2.0/dbhome_1:Y
