NTP-server时间同步配置与排错CentOS 6.7 x64

目录

第1章 ntp时间服务器同步环境准备... 2

1.1 检查系统是否安装ntp服务... 2

1.2 配置ntp服务的配置文件... 2

1.3 重启ntp服务... 3

1.4 检查ntp服务是否运行... 4

1.5 检查ntp服务器与上层授时服务器的连通与状态... 4

1.6 ntp服务重启写入开机启动... 4

第2章客户端时间同步配置... 5

2.1 修改本地hosts文件... 5

2.2 ~检查命令行内是否能够同步... 5

2.3 写入定时任务中... 5

2.4 验证时间同步定时任务... 5

第3章故障排错... 6

3.1 防火墙没有关闭... 6（非常重要）

3.2 ntp-server中ntp服务没有开启... 6

第1章 ntp时间服务器同步环境准备

1.1 检查系统是否安装ntp服务

[root@schools02 ~]# rpm -qa ntp 没有显示结果，系统没有安装ntp服务

[root@schools02 ~]# yum install ntp �y 安装ntp服务 �y不显示报错

Loaded plugins: fastestmirror

Setting up Install Process

base| 3.7 kB 00:00

base/primary_db| 4.7 MB 00:03

Dependency Installed:

libedit.x86_64 0:2.11-4.20080712cvs.1.el6 ntpdate.x86_640:4.2.6p5-10.el6.centos.1

Complete! 安装完毕

[root@schools02 ~]# rpm -qa ntp

ntp-4.2.6p5-10.el6.centos.1.x86_64 安装成功

1.2 配置ntp服务的配置文件

[root@schools02 ~]# vi /etc/ntp.conf

# For more information about this file,see the manpages

# ntp.conf(5),ntp_acc(5),ntp_auth(5),ntp_clock(5),ntp_misc(5),ntp_mon(5).

driftfile /var/lib/ntp/drift

# Permit time synchronization with our time source,but do not

# permit the source to query or modify the serviceon this system.

restrict default kod nomodify notrap noquery 默认是拒绝所有客户机同步时间在下一行加入：

restrict 172.16.2.0 mask 255.255.255.0 nomodify 仅在此网段的客户机可以同步时间

restrict -6 default kod nomodify notrap nopeernoquery

# Permit all access over the loopbackinterface. This could

# be tightened as well,but to do so would effectsome of

# the administrative functions.

restrict 127.0.0.1

restrict -6 ::1

# Hosts on local network are less restricted.

#restrict 172.16.2.0 mask 255.255.255.0 nomodifynotrap

# Use public servers from the pool.ntp.org project.

# Please consider joining the pool(http://www.pool.ntp.org/join.html).

server 0.centos.pool.ntp.org prefer 设置首选的ntp �server同步服务器

server 1.centos.pool.ntp.org iburst

server 2.centos.pool.ntp.org iburst

server 3.centos.pool.ntp.org iburst

#broadcast 192.168.1.255 autokey # broadcast server

#broadcastclient# broadcastclient

#broadcast 224.0.1.1 autokey # multicast server

#multicastclient 224.0.1.1 # multicast client

#manycastserver 239.255.254.254 # manycast server

#manycastclient 239.255.254.254 autokey # manycastclient

# Enable public key cryptography.

#crypto

includefile /etc/ntp/crypto/pw

# Key file containing the keys and key identifiersused when operating

# with symmetric key cryptography.

keys /etc/ntp/keys

# Specify the key identifiers which are trusted.

#trustedkey 4 8 42

#statistics clockstats cryptostats loopstatspeerstats

"/etc/ntp.conf" 53L,1771C written

此配置环境是客户机ntp-server可以访问外网。既有上层的ntp-server

在此文档里边仅需更改限制时间同步的网段即可

1.3 重启ntp服务

[root@schools02 ~]# /etc/init.d/ntpd restart

Shutting down ntpd: [ OK ]

Starting ntpd: [OK ]

1.4 检查ntp服务是否运行

[root@schools02 ~]# netstat -lntup|grep ntp

udp0 0 172.16.2.146:123 0.0.0.0:* 1599/ntpd

udp0 0 127.0.0.1:123 0.0.0.0:* 1599/ntpd

udp0 0 0.0.0.0:123 0.0.0.0:* 1599/ntpd

udp0 0 ::1:123 :::* 1599/ntpd

udp0 0 :::123 :::* 1599/ntpd

1.5 检查ntp服务器与上层授时服务器的连通与状态

[root@schools02 ~]# ntpstat

synchronised to NTP server (202.112.29.82) atstratum 3

timecorrect to within 3995 ms

pollingserver every 64 s

[root@schools02 ~]# ntpq -p

remote refid st t when poll reach delayoffset jitter

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

*time6.aliyun.co 10.137.38.86 2 u18 64 121.614 18.914 0.000

202.118.1.130.INIT. 16 u -64 0 0.0000.000 0.000

dns1.synet.edu. 202.118.1.46 2 u6 64 192.939 -2.845 7.267

1.6 ntp服务重启写入开机启动

[root@schools02 ~]# echo "/etc/init.d/ntpdrestart" >>/etc/rc.local 开机后服务可以自动重启，开始服务

[root@schools02 ~]# cat /etc/rc.local

#!/bin/sh

# This script will be executed *after* all theother init scripts.

# You can put your own initialization stuff in hereif you don't

# want to do the full Sys V style init stuff.

touch /var/lock/subsys/local

/etc/init.d/ntpd restart

第2章 客户端时间同步配置

2.1 修改本地hosts文件

[root@schools02 ~]# vi /etc/hosts

127.0.0.1localhost localhost.localdomain localhost4 localhost4.localdomain4

::1localhost localhost.localdomain localhost6 localhost6.localdomain6

172.16.2.146ntp-server

"/etc/hosts" 3L,183C written

2.2 检查命令行内是否能够同步

[root@schools02 ~]# ntpdate 172.16.2.146

5 Sep01:44:54 ntpdate[1609]: adjust time server 172.16.2.146 offset 0.058518 sec

[root@schools02 ~]# ntpdate ntp-server

5 Sep01:46:47 ntpdate[1611]: adjust time server 172.16.2.146 offset 0.003564 sec

2.3 写入定时任务中

[root@schools02 ~]# echo "* * * * * /usr/sbin/ntpdate ntp-server" >>/var/spool/cron/root

[root@schools02 ~]# crontab -l

* * * * * /usr/sbin/ntpdatentp-server

[root@schools02 ~]# tail -f /var/log/cron

Sep 501:51:02 schools02 CROND[1617]: (root) CMD (/bin/sh /usr/sbin/ntpdatentp-server)

2.4 验证时间同步定时任务

[root@schools02 ~]# date -s 20160302

Wed Mar 200:00:00 CST 2016

[root@schools02 ~]# tail -f /var/log/cron

Sep 502:03:03 schools02 CROND[1774]: (root) CMD (/usr/sbin/ntpdate ntp-server)

[root@schools02 ~]# date

Mon Sep 502:03:06 CST 2016 更新完毕

第3章 故障排错

3.1 防火墙没有关闭

root@schools02 ~]# chkconfig iptables on 打开ntp-server服务器防火墙

[root@schools02 ~]# /etc/init.d/ntpd restart

Shutting down ntpd: [ OK ]

Starting ntpd: [OK ]

[root@schools02 ~]# chkconfig --list|grep ntp

ntpd0:off 1:off 2:off3:off 4:off 5:off6:off

ntpdate0:off 1:off 2:off3:off 4:off 5:off6:off

[root@schools02 ~]# chkconfig --list|grep iptables

iptables0:off 1:off 2:on3:on 4:on 5:on6:off

[root@schools02 ~]# ntpdate ntp-server 客户端无法同步时间

5 Sep02:11:08 ntpdate[1849]: no server suitable for synchronization found

3.2 ntp-server中ntp服务没有开启

[root@schools02 ~]# pkill ntpd

[root@schools02 ~]# netstat -lntup|grep ntpd

[root@schools02 ~]# ntpdate ntp-server 客户端失败

5 Sep02:14:39 ntpdate[1868]: no server suitable for synchronization found

[root@schools02 ~]# service ntpd start

Starting ntpd: [OK ] [root@schools02 ~]# netstat-lntup|grep ntpd

udp0 0 172.16.2.146:123 0.0.0.0:* 2056/ntpd

udp0 0 127.0.0.1:123 0.0.0.0:* 2056/ntpd

udp0 0 0.0.0.0:123 0.0.0.0:* 2056/ntpd

root@schools02 ~]# ntpdate ntp-server 客户端成功同步

5 Seadjusttime server 172.16.2.146 offset 0.003626 sec

最后放大招：所有的检查都做了，还不能同步。就重启一下系统。