一、实验环境

操作系统：CentOS7.x 

ntp_sever：192.168.1.110

ntp_client：192.168.1.120

二、软件安装和防火墙设置

在ntp_sever 和 ntp_client

# yum -y install  ntp ntpdate

在ntp_sever 和 ntp_client均需要开放123/udp端口

# firewall-cmd --zone=public --add-port=123/udp --permanent

# firewall-cmd --reload

三、服务端配置

# vim  /etc/ntp.conf

########################################

driftfile /var/lib/ntp/drift

restrict default nomodify notrap nopeer noquery

restrict 127.0.0.1

restrict ::1

restrict 192.168.1.0 mask 255..255.255.0 nomodify notrap

server 192.168.1.110 iburst

server 127.127.1.0

fudge 127.127.1.0 stratum 10

interface ignore  wildcard

interface listen  192.168.1.110

interface listen  127.0.0.1

includefile /etc/ntp/crypto/pw

keys /etc/ntp/keys

disable monitor

##########################################

# systemctl start ntpd

# systemctl enable ntpd

# firewall-cmd --zone=public --add-port=123/udp --permanent

# firewall-cmd --reload

四、客户端配置

# vim  /etc/ntp.conf

#########################

driftfile /var/lib/ntp/drift

restrict default nomodify notrap nopeer noquery

restrict 127.0.0.1

restrict ::1

server 192.168.1.110 iburst

restrict 192.168.1.110 nomodify notrap noquery

server 127.127.1.0

fudge 127.127.1.0 stratum 10

includefile /etc/ntp/crypto/pw

keys /etc/ntp/keys

disable monitor

#########################

# ntpdate 192.168.1.110

# systemctl  start   ntpd

# systemctl enable ntpd