Check Date of your Machine which includes Time.
date
Check Current TimeZone.
date +’%Z %z’
Change TimeZone in CentOS 6
Backup current TimeZone in /root directory
cp /etc/localtime /root/timezone.old
Create Symbolic Link to your desired TimeZone
My desired TimeZone is IST
ln -sf /usr/share/zoneinfo/Asia/Kolkata /etc/localtime
Check Date
date
Verify TimeZone
date +’%Z %z’
Change TimeZone in CentOS 7
List all TimeZone
timedatectl list-timezones
List TimeZones of Asia
timedatectl list-timezones | grep Asia
Change TimeZone to IST
timedatectl set-timezone Asia/Kolkata
Check Date
date
Check TimeZone
date +’%Z %z’