Auto Start/Shutdown Oracle 11g on CEntOS

Modify /etc/oratab and Replace N with Y for enabling Oracle Startup at Boot.

TESTDB:/u01/app/oracle/product/11.2.0/db_1:N
to 
TESTDB:/u01/app/oracle/product/11.2.0/db_1:Y

Create /etc/init.d/oracle file with following codes vi /etc/init.d/oracle. Must change ORACLE_HOME, ORACLE_SID

#!/bin/sh
#
# /etc/rc.d/init.d/oracle
# Description: Starts and stops the Oracle database, listeners and Enterprise Manager
# See how we were called.

export ORACLE_HOME=/u01/app/oracle/product/11.2.0/db_1
export ORACLE_SID=TESTDB

case "$1" in
start)
echo "Starting Oracle"
echo "—————————————————-" >> /var/log/oracle
date +"! %T %a %D : Starting Oracle Databases as part of system up." >> /var/log/oracle
echo "—————————————————-" >> /var/log/oracle
echo -n "Starting Oracle Databases: "
su - oracle -c ${ORACLE_HOME}/bin/dbstart >> /var/log/oracle
echo "Done."
echo -n "Starting Oracle Listeners: "
su - oracle -c "${ORACLE_HOME}/bin/lsnrctl start" >> /var/log/oracle
echo "Done."
echo -n "Starting Oracle Enterprise Manager: "
su - oracle -c "${ORACLE_HOME}/bin/emctl start dbconsole" >> /var/log/oracle
echo "Done."
echo ""
echo "—————————————————-" >> /var/log/oracle
date +"! %T %a %D : Finished." >> /var/log/oracle
echo "—————————————————-" >> /var/log/oracle
touch /var/lock/subsys/oracle
;;
stop)
echo "Shutting Down Oracle"
echo "—————————————————-" >> /var/log/oracle
date +"! %T %a %D : Shutting Down Oracle Databases as part of system down." >> /var/log/oracle
echo "—————————————————-" >> /var/log/oracle
echo -n "Shutting Down Oracle Enterprise Manager: "
su - oracle -c "${ORACLE_HOME}/bin/emctl stop dbconsole" >> /var/log/oracle
echo "Done."
echo -n "Shutting Down Oracle Listeners: "
su - oracle -c "${ORACLE_HOME}/bin/lsnrctl stop" >> /var/log/oracle
echo "Done."
rm -f /var/lock/subsys/oracle
echo -n "Shutting Down Oracle Databases: "
su - oracle -c ${ORACLE_HOME}/bin/dbshut >> /var/log/oracle
echo "Done."
echo ""
echo "—————————————————-" >> /var/log/oracle
date +"! %T %a %D : Finished." >> /var/log/oracle
echo "—————————————————-" >> /var/log/oracle
;;
restart)
echo "Restarting Oracle"
echo "—————————————————-" >> /var/log/oracle
date +"! %T %a %D : Restarting Oracle Databases as part of system up." >> /var/log/oracle
echo "—————————————————-" >> /var/log/oracle
echo -n "Restarting Oracle Databases: "
su - oracle -c ${ORACLE_HOME}/bin/dbshut >> /var/log/oracle
su - oracle -c ${ORACLE_HOME}/bin/dbstart >> /var/log/oracle
echo "Done."
echo -n "Restarting Oracle Listeners: "
su - oracle -c "${ORACLE_HOME}/bin/lsnrctl stop" >> /var/log/oracle
su - oracle -c "${ORACLE_HOME}/bin/lsnrctl start" >> /var/log/oracle
echo "Done."
echo -n "Restarting Oracle Enterprise Manager: "
su - oracle -c "${ORACLE_HOME}/bin/emctl stop dbconsole" >> /var/log/oracle
su - oracle -c "${ORACLE_HOME}/bin/emctl start dbconsole" >> /var/log/oracle
echo "Done."
echo ""
echo "—————————————————-" >> /var/log/oracle
date +"! %T %a %D : Finished." >> /var/log/oracle
echo "—————————————————-" >> /var/log/oracle
touch /var/lock/subsys/oracle
;;
*)
echo "Usage: oracle {start|stop|restart}"
exit 1
esac

Make the script file executable. Execute following command to change permission.

chmod 755 /etc/init.d/oracle

The following commands will ensure that the databases will come up in runlevels 2,3,4 and 5

ln -s /etc/rc.d/init.d/oracle /etc/rc.d/rc2.d/S99oracle
ln -s /etc/rc.d/init.d/oracle /etc/rc.d/rc3.d/S99oracle
ln -s /etc/rc.d/init.d/oracle /etc/rc.d/rc4.d/S99oracle
ln -s /etc/rc.d/init.d/oracle /etc/rc.d/rc5.d/S99oracle

To stop the databases on reboot or restart we need the following links

ln -s /etc/rc.d/init.d/oracle /etc/rc.d/rc0.d/K01oracle
ln -s /etc/rc.d/init.d/oracle /etc/rc.d/rc6.d/K01oracle