NTP called the Network Time Protocol, namely the Network Time Protocol. It is a protocol used to synchronize the computer time. It enables a server computer to make the synchronization clock source or may be provided with high precision time correction (on the LAN with the standard time less than 1 ms, several tens of milliseconds on the WAN), but also to prevent malicious identifiable manner by the encryption protocol *** .
Experimental environment
two virtual machines NTP time server 192.168.43.57
host 192.168.43.29
Server
Install ntp
yum install -y ntp
Edit the configuration file vim /etc/ntp.conf
This line to comment
#restrict default nomodify notrap nopeer noquery
Open ntp service: systemctl start ntpd
Client
Install ntp service: yum -y install ntp
Modify the configuration file, add the upper time server
Open ntp service: service ntpd start
Synchronization time: ntpdate 192.168.43.57