Linux ntp配置

Linux NTP配置

环境

Cenos 6.6 X86_64

ntp服务端

配置/etc/ntpd.cn

修改/etc/ntpd.cnf,完成后结果如下,我们使用grep -v “^#” /etc/ntp.conf查看下

driftfile /var/lib/ntp/drift

restrict default kod nomodify notrap nopeer noquery
restrict -6 default kod nomodify notrap nopeer noquery

restrict 127.0.0.1 
restrict -6 ::1

restrict 192.168.31.0 mask 255.255.255.0 nomodify notrap

server 0.pool.ntp.org
server 1.pool.ntp.org
server 2.pool.ntp.org
server 3.pool.ntp.org
server cn.pool.ntp.org prefer

server  127.127.1.0     # local clock
fudge   127.127.1.0 stratum 10



includefile /etc/ntp/crypto/pw

keys /etc/ntp/keys

启动ntpd服务

service ntpd start

添加防火墙

修改/etc/sysconfig/iptables添加如下条目，开放udp 123端口

-A INPUT -p udp -m state --state NEW -s 192.168.31.0/24 --dport 123 -j ACCEPT 

查看服务状态

查看服务是否开启
service ntpd status

ntpstat查看运行状态,ntp服务是否与上层联机
[root@testsrv ~]# ntpstat 
unsynchronised
   polling server every 64 s

ntpq列出上层ntp状态
[root@testsrv~]# ntpq -p
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
*news.neu.edu.cn 202.118.1.47     2 u   28   64   37  127.321  201.540  98.977
+dns1.synet.edu. 202.118.1.46     2 u   29   64   27  102.763  186.822  93.444
 dns2.synet.edu. 202.118.1.46     2 u   39   64   51  457.176  359.954 172.589
 LOCAL(0)        .LOCL.          10 l  108   64   76    0.000    0.000   0.000

ntp客户端

加入定时任务,每小时的第1分钟同步时间

crontab -e

1 * * * * /usr/sbin/ntpdate 192.168.31.10 && /sbin/hwclock --systohc

重启下定时任务
service crond restart