What is NTP?
NTP is the Network Time Protocol, a protocol used to synchronize the time of network devices (such as computers and mobile phones).
Alibaba Cloud's NTP server:- ntp1.aliyun.com
- ntp2.aliyun.com
- ntp3.aliyun.com
- ntp4.aliyun.com
First, the timedatectl command to view the current time zone:
[root@localhost Asia]# timedatectl
Local time: Tue 2018-04-24 07:29:13 CST
Universal time: Mon 2018-04-23 23:29:13 UTC
RTC time: Mon 2018-04-23 23:29:13
Time zone: America/New_York (CST, +0800)
NTP enabled: yes
NTP synchronized: yes
RTC in local TZ: no
DST active: n/a
[root@localhost Asia]#
2. Detailed explanation of timedatectl command
[root@localhost Asia]# timedatectl --help
timedatectl [OPTIONS...] COMMAND ...
Query or change system time and date settings.
-h --help Show this help message
--version Show package version
--no-pager Do not pipe output into a pager
--no-ask-password Do not prompt for password
-H --host=[USER@]HOST Operate on remote host
-M --machine=CONTAINER Operate on local container
--adjust-system-clock Adjust system clock when changing local RTC mode
Commands: status Show current time settings set-time TIME Set system time set-timezone ZONE Set system time zone
list-timezones Show known time zones
set-local-rtc BOOL Control whether RTC is in local time
set-ntp BOOL Control whether NTP is enabled
3. View all timezones timedatectl list-timezones
[root@localhost Asia]# timedatectl list-timezones|grep Shanghai
Asia/Shanghai
[root@localhost Asia]#
4. Change to Shanghai timezone timedatectl set-timezone Asia/Shanghai
[root@localhost Asia]# timedatectl status
Local time: Tue 2018-04-24 07:36:56 CST
Universal time: Mon 2018-04-23 23:36:56 UTC
RTC time: Mon 2018-04-23 23:36:56
Time zone: Asia/Shanghai (CST, +0800)
NTP enabled: yes
NTP synchronized: yes
RTC in local TZ: no
DST active: n/a
[root@localhost Asia]#
5. Synchronize time server
Install: #yum -y install ntpdate
# systemctl enable ntpd
#systemctl start ntpd
#ntpdate ntp1.aliyun.com
Set NTP to enable timedatectl set-ntp yes
set NTP off timedatectl set-ntp no
The timedatectl command can also set the time and date
set date format timedatectl set-time YYYY-MM-DD
Set time format timedatectl set-time HH:MM:SS