description: as timezone is the basis of system calculation for all time related parameters, it is very important to be consistent and accurate.
steps to follow:
1. using putty to login to terminal linux file system. (login id: parktron, password: pt12885568
2. "su" to change user to root.
3. "mount -o remount,rw /"
4. "rm /etc/localtime"
5. "ln -s /usr/share/zoneinfo/[timezone_file_wanted] /etc/localtime"