# timedatectl Local time: Tue 2017-06-13 05:17:20 EDT Universal time: Tue 2017-06-13 09:17:20 UTC RTC time: Tue 2017-06-13 09:17:20 Time zone: America/New_York (EDT, -0400) NTP enabled: yes NTP synchronized: yes RTC in local TZ: no DST active: yes Last DST change: DST began at Sun 2017-03-12 01:59:59 EST Sun 2017-03-12 03:00:00 EDT Next DST change: DST ends (the clock jumps one hour backwards) at Sun 2017-11-05 01:59:59 EDT Sun 2017-11-05 01:00:00 EST
Network Time Protocol (NTP)
The Network Time Protocol (NTP) is a standard way for machines to provide and obtain correct time information on the Internet. A machine may get accurate time information from public NTP services on the Internet such as the NTP Pool Project. A high-quality hardware clock to serve accurate time to local clients is another option.
The timedatectl command shows an overview of the current time-related system settings, including current time, time zone, and NTP synchronization settings of the system.
# timedatectl list-timezones # timedatectl set-timezone Asia/Shanghai # timedatectl Local time: Tue 2017-06-13 17:23:41 CST Universal time: Tue 2017-06-13 09:23:41 UTC RTC time: Tue 2017-06-13 09:23:41 Time zone: Asia/Shanghai (CST, +0800) NTP enabled: yes NTP synchronized: yes RTC in local TZ: no DST active: n/a
# timedatectl set-ntp false # timedatectl set-ntp true