Linux服务器配置---ntp

[root@localhost ~]# rpm -qa | grep ntp         //检测是否已安装，这个软件默认是安装的

ntpdate-4.2.6p5-1.el6.centos.i686

fontpackages-filesystem-1.41-1.1.el6.noarch

ntp-4.2.6p5-1.el6.centos.i686

[root@localhost ~]# 

[root@localhost wj]# gedit /etc/xinetd.d/telnet

#server 0.centos.pool.ntp.org iburst

#server 1.centos.pool.ntp.org iburst

#server 2.centos.pool.ntp.org iburst

#server 3.centos.pool.ntp.org iburst    //上面这几个不要了

server ntp1.aliyun.com                    //阿里云时间服务器

server ntp2.aliyun.com

server ntp3.aliyun.com

server ntp4.aliyun.com

[root@localhost wj]# gedit /etc/sysconfig/iptables

-A INPUT -m state --state NEW -m udp -p udp --dport 123 -j ACCEPT 

[root@localhost wj]# service iptables restart

iptables：将链设置为政策 ACCEPT：filter nat                [确定]

iptables：清除防火墙规则：                                 [确定]

iptables：正在卸载模块：                                   [确定]

iptables：应用防火墙规则：                                 [确定]

iptables：载入额外模块：nf_conntrack_ftp                   [确定]

[root@localhost wj]# service ntpd restart

关闭ntpd：                                               [确定]

正在启动ntpd：                                            [确定]

[root@localhost wj]# ntpq -p

     remote           refid      st t when poll reach   delay   offset  jitter

==============================================================================

 120.25.115.20   10.137.53.7      2 u    4   64    1   26.132  188282.   0.000

 203.107.6.88    100.107.25.114   2 u    3   64    1   83.645  188285.   0.000

[root@localhost wj]# ntpdate aliyun.com

16 Aug 10:07:03 ntpdate[20193]: the NTP socket is in use, exiting    //如果遇到此错误，请按照下面的方式执行

[root@localhost wj]# lsof -i:123

COMMAND   PID USER   FD   TYPE DEVICE SIZE/OFF NODE NAME

ntpd    20187  ntp   16u  IPv4 262711      0t0  UDP *:ntp         

ntpd    20187  ntp   17u  IPv6 262712      0t0  UDP *:ntp 

ntpd    20187  ntp   18u  IPv4 262718      0t0  UDP localhost:ntp 

ntpd    20187  ntp   19u  IPv4 262719      0t0  UDP 192.168.0.119:ntp 

ntpd    20187  ntp   20u  IPv6 262720      0t0  UDP localhost:ntp 

ntpd    20187  ntp   21u  IPv6 262721      0t0  UDP [fe80::a00:27ff:fe14:3357]:ntp 

[root@localhost wj]# kill -9 20187     //杀掉上面的进程

[root@localhost wj]# ntpdate 202.112.29.82

16 Aug 10:13:21 ntpdate[20212]: adjust time server 202.112.29.82 offset 0.006454 sec