ntplinux

vim /etc/ntp.con

restrict 192.168.0.0 mask 255.255.255.0 nomodify notrap 允许的网段

server 　时间服务 132.163.4.102

service ntpd restart

刚配置好NTP 连接不上来的要等一下

netstat -ntulp |grep :12

iptables -F

iptables -L

有默认规则

iptables -P INPUT ACCEPT

iptables -P OUTPUT ACCEPT

iptables -A INPUT -s 192.168.0.0/24 -p udp --dport 123 -j ACCEPT 写规则 因为ntp用的是23端口所以要开启

查看

chkconfig ntpd on  重启还生效

chkcofnig ntpdate on

ntpdate －u 132.163.4.101 时间服务器地址

ntpdate -u 192.168.0.110   本机IP 地址

crontab -e

*/5 * * * * /usr/sbin/ntpdate -u 192.168.0.253

!which ntpdate  查看路径

chkconfig |grep ntpd

看下 ntpd 服务器是否开启开机

国内常用NTP服务器地址及IP

time-a.timefreq.bldrdoc.gov 132.163.4.101 NIST, Boulder, Colorado可用

time-b.timefreq.bldrdoc.gov 132.163.4.102 NIST, Boulder, Colorado

time-c.timefreq.bldrdoc.gov 132.163.4.103 NIST, Boulder, Colorado

utcnist.colorado.edu 128.138.140.44 University of Colorado, Boulder

time.nist.gov 192.43.244.18 NCAR, Boulder, Colorado

time-nw.nist.gov 131.107.1.10 Microsoft, Redmond, Washington

nist1.symmetricom.com 69.25.96.13 Symmetricom, San Jose, California

nist1-dc.glassey.com 216.200.93.8 Abovenet, Virginia

nist1-ny.glassey.com 208.184.49.9 Abovenet, New York City

nist1-sj.glassey.com 207.126.98.204 Abovenet, San Jose, California

nist1.aol-ca.truetime.com 207.200.81.113 TrueTime, AOL facility, Sunnyvale, California

nist1.aol-va.truetime.com 64.236.96.53 TrueTime, AOL facility, Virginia