centos7安装ntp服务

1. 安装ntp服务

   //查询是否安装了ntp
   rpm -qa | grep ntp
   yum install -y ntp
   

2. 修改所有节点的ntp.conf (vi /etc/ntp.conf), 添加以下内容

   //当前节点IP地址
   restrict 10.0.32.20 nomodify notrap nopeer noquery          
   //集群所在网段的网关（Gateway），子网掩码（Genmask）	  
   restrict 10.0.32.1 mask 255.255.255.0 nomodify notrap     
   

   ps: 查询网关,掩码:

   cat /etc/sysconfig/network-scripts/ifcfg-eth0  
   

3. 选择一个主节点，修改ntp.conf
   在server部分添加以下部分，并注释掉server 0 ~ n

   //因为是内网环境所以使用本机时间, 也可使用网络时间
   server 127.127.1.0  
   fudge 127.127.1.0 stratum 10
   

4. 修改主节点以外的ntp.conf
   在server部分添加如下语句，将server指向主节点。

   server <主节点IP> prefer
   

5. 启动ntp

   systemctl start ntpd
   

6. 设置开机自启

   chkconfig ntpd on
   

7. 查询同步状态

   ntpstat  
   

   ntp同步需要5-10分钟,服务刚启动时ntpstat显示unsynchronized…是正常现象
   显示如下内容表示同步成功

   synchronised to NTP server (x.x.x.x) at stratum 12
   time correct to within 24 ms
   polling server every 256 s

server配置示例:

driftfile /var/lib/ntp/drift

restrict default nomodify notrap nopeer noquery

restrict 127.0.0.1 
restrict ::1

restrict 10.0.32.202 nomodify 
restrict 10.0.32.254 mask 255.255.255.0 nomodify notrap

server 127.127.1.0 
fudge 127.127.1.0  stratum 10

includefile /etc/ntp/crypto/pw

keys /etc/ntp/keys

disable monitor

logfile /var/log/ntp.log 

client配置示例:

driftfile /var/lib/ntp/drift

restrict default nomodify notrap nopeer noquery

restrict 127.0.0.1 
restrict ::1

restrict 10.0.32.203 nomodify notrap nopeer noquery
restrict 10.0.32.254 mask 255.255.255.0 nomodify notrap

server 10.0.32.202 prefer

includefile /etc/ntp/crypto/pw

keys /etc/ntp/keys

disable monitor

logfile /var/log/ntp.log