Synchronise time

timedatectl

$ sudo timedatectl
$ sudo timedatectl list-timezones

$ sudo timedatectl set-timezone Asia/Shanghai
$ sudo timedatectl set-timezone America/Montreal

$ sudo rm -rf /etc/localtime
$ sudo ln -s /usr/share/zoneinfo/America/Montreal /etc/localtime

$ sudo timedatectl set-timezone EST	# Timezone as EST
$ sudo timedatectl set-timezone UTC	# Timezone as UTC

$ sudo timedatectl set-ntp yes
$ sudo timedatectl set-ntp no

$ sudo timedatectl set-time YYYY-MM-DD
$ sudo timedatectl set-time HH:MM:SS

timesyncd

$ systemctl status systemd-timesyncd

$ sudo vim /etc/systemd/timesyncd.conf
OR
$ cd /etc/systemd/timesyncd.conf.d/