///
/// 安装
///
[root@wode012 mysql]# yum install ntp
已加载插件：fastestmirror, langpacks
Repository base is listed more than once in the configuration
Repository updates is listed more than once in the configuration
Repository extras is listed more than once in the configuration
Repository centosplus is listed more than once in the configuration
Repository contrib is listed more than once in the configuration
Loading mirror speeds from cached hostfile
* base: mirrors.aliyun.com
* extras: mirrors.aliyun.com
* updates: mirrors.aliyun.com
软件包 ntp-4.2.6p5-19.el7.centos.3.x86_64 已安装并且是最新版本
无须任何处理
[root@wode012 mysql]#
///
/// vi /etc/ntp.conf
///
restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap
server time.lib.tsinghua.edu.cn
server cn.pool.ntp.org
///
/// systemctl enable/status/start
///
[root@wode012 etc]# systemctl enable ntpd.service
[root@wode012 etc]# systemctl status ntpd.service
ntpd.service - Network Time Service
Loaded: loaded (/usr/lib/systemd/system/ntpd.service; enabled)
Active: inactive (dead)
[root@wode012 etc]# systemctl start ntpd.service
[root@wode012 etc]# systemctl status ntpd.service
ntpd.service - Network Time Service
Loaded: loaded (/usr/lib/systemd/system/ntpd.service; enabled)
Active: active (running) since 六 2015-11-14 23:48:34 CST; 2s ago
Process: 26192 ExecStart=/usr/sbin/ntpd -u ntp:ntp $OPTIONS (code=exited, status=0/SUCCESS)
Main PID: 26193 (ntpd)
CGroup: /system.slice/ntpd.service
└─26193 /usr/sbin/ntpd -u ntp:ntp -g
///
/// firewall
///
[root@wode012 services]# firewall-cmd --add-service=ntp --permanent
success
[root@wode012 services]# firewall-cmd --list-all
public (default, active)
interfaces: enp3s0f0 enp3s0f1
sources:
services: dhcpv6-client mysql ssh
ports: 8703/tcp
masquerade: no
forward-ports:
icmp-blocks:
rich rules:
[root@wode012 services]# firewall-cmd --reload
success
[root@wode012 services]# firewall-cmd --list-all
public (default, active)
interfaces: enp3s0f0 enp3s0f1
sources:
services: dhcpv6-client mysql ntp ssh
ports:
masquerade: no
forward-ports:
icmp-blocks:
rich rules:
[root@wode012 services]#
// for old version, iptables
iptables -A INPUT -p udp -dport 123 -j ACCEPT
///
/// check on server
///
[root@wode012 etc]# ntpq -p
remote refid st t when poll reach delay offset jitter
==============================================================================
web.lib.tsinghu .INIT. 16 u - 64 0 0.000 0.000 0.000
+news.neu.edu.cn 202.118.1.46 2 u 24 64 1 12.675 -5.860 0.000
+dns1.synet.edu. 202.118.1.46 2 u 14 64 1 12.546 -5.778 1.238
*202.118.1.130 202.118.1.46 2 u 13 64 1 12.399 -5.711 0.797
dns.sjtu.edu.cn .INIT. 16 u - 64 0 0.000 0.000 0.000
///
/// test on client
///
#!/bin/bash
# sync time
/usr/sbin/ntpdate 192.168.1.134
# write to hw
/usr/sbin/hwclock -w
