For setting the IST Timezone on the Ec2 instance
1. vi /etc/sysconfig/clock
ZONE="Asia/Kolkata"
UTC=false
2. sudo mv /etc/localtime /etc/localtime_old
3. sudo ln -s /usr/share/zoneinfo/Asia/Kolkata /etc/localtime
4. sudo reboot
Restart is necessary for all the services to take the updated timezone.
