2020/12/17 ubuntu16.04 NTP时间同步配置

2022-08-05 19:43:51

ntp时间同步，大体步骤是将服务器端和客户端配置好，然后设定同步的频率，记得重新运行ntp服务，重启即可。

步骤总结如下：

一 服务器端（server）

1. 安装ntp与ntpdate

$ sudo apt-get install ntp

$ sudo apt-get install ntpdate

2. server服务器端修改配置文件

$ sudo gedit /etc/ntp.conf

然后对照以下内容修改配置文件：

# /etc/ntp.conf, configuration for ntpd; see ntp.conf(5) for help

 

driftfile /var/lib/ntp/ntp.drift

 

# Enable this if you want statistics to be logged.

#statsdir /var/log/ntpstats/

 

statistics loopstats peerstats clockstats

filegen loopstats file loopstats type day enable

filegen peerstats file peerstats type day enable

filegen clockstats file clockstats type day enable

 

# Specify one or more NTP servers.

 

# Use servers from the NTP Pool Project. Approved by Ubuntu Technical Board

# on 2011-02-08 (LP: #104525). See http://www.pool.ntp.org/join.html for

# more information.

#linux自带的时间同步，需要注释掉

#pool 0.ubuntu.pool.ntp.org iburst

#pool 1.ubuntu.pool.ntp.org iburst

#pool 2.ubuntu.pool.ntp.org iburst

#pool 3.ubuntu.pool.ntp.org iburst

 

# Use Ubuntu's ntp server as a fallback.

#pool ntp.ubuntu.com

 

# Access control configuration; see /usr/share/doc/ntp-doc/html/accopt.html for

# details.  The web page <http://support.ntp.org/bin/view/Support/AccessRestrictions>

# might also be helpful.

#

# Note that "restrict" applies to both servers and clients, so a configuration

# that might be intended to block requests from certain clients could also end

# up blocking replies from your own upstream servers.

 

# By default, exchange time with everybody, but don't allow configuration.

restrict -4 default kod notrap nomodify nopeer noquery limited

restrict -6 default kod notrap nomodify nopeer noquery limited

 

# Local users may interrogate the ntp server more closely.

restrict 127.0.0.1

restrict ::1

#因为是内网，所以用本地时间做为服务器时间，注意这里不是127.0.0.1

server 127.127.1.0

fudge 127.127.1.0 stratum 8

 

#开放192.168.8.0 整个网段，即在这个网段的所有机器都可以使用 214 作为时间同步服务端

 

restrict 192.168.0.0 mask 255.255.255.0 nomodify notrap

 

# Needed for adding pool entries

restrict source notrap nomodify noquery

 

# Clients from this (example!) subnet have unlimited access, but only if

# cryptographically authenticated.

#restrict 192.168.123.0 mask 255.255.255.0 notrust

 

 

# If you want to provide time to your local subnet, change the next line.

# (Again, the address is an example only.)

#broadcast 192.168.123.255

 

# If you want to listen to time broadcasts on your local subnet, de-comment the

# next lines.  Please do this only if you trust everybody on the network!

#disable auth

#broadcastclient

 

#Changes recquired to use pps synchonisation as explained in documentation:

#http://www.ntp.org/ntpfaq/NTP-s-config-adv.htm#AEN3918

 

#server 127.127.8.1 mode 135 prefer    # Meinberg GPS167 with PPS

#fudge 127.127.8.1 time1 0.0042        # relative to PPS for my hardware

 

#server 127.127.22.1                   # ATOM(PPS)

#fudge 127.127.22.1 flag3 1            # enable PPS API

3. 设置完成退出保存，然后重启ntp服务

$ sudo service ntp restart

至此，服务器端ntp配置完成。

二 客户端（client）

1. 与服务器端相同，需要ntp与ntpdate

$ sudo apt-get install ntp

$ sudo apt-get install ntpdate

2. 修改配置文件，client的配置相对简单

$ sudo gedit  /etc/ntp.conf

对照以下内容修改

# /etc/ntp.conf, configuration for ntpd; see ntp.conf(5) for help

 

driftfile /var/lib/ntp/ntp.drift

 

# Enable this if you want statistics to be logged.

#statsdir /var/log/ntpstats/

 

statistics loopstats peerstats clockstats

filegen loopstats file loopstats type day enable

filegen peerstats file peerstats type day enable

filegen clockstats file clockstats type day enable

 

# Specify one or more NTP servers.

 

# Use servers from the NTP Pool Project. Approved by Ubuntu Technical Board

# on 2011-02-08 (LP: #104525). See http://www.pool.ntp.org/join.html for

# more information.

#linux自带的时间同步，需要注释掉

#pool 0.ubuntu.pool.ntp.org iburst

#pool 1.ubuntu.pool.ntp.org iburst

#pool 2.ubuntu.pool.ntp.org iburst

#pool 3.ubuntu.pool.ntp.org iburst

 

# Use Ubuntu's ntp server as a fallback.

#pool ntp.ubuntu.com

 

# Access control configuration; see /usr/share/doc/ntp-doc/html/accopt.html for

# details.  The web page <http://support.ntp.org/bin/view/Support/AccessRestrictions>

# might also be helpful.

#

# Note that "restrict" applies to both servers and clients, so a configuration

# that might be intended to block requests from certain clients could also end

# up blocking replies from your own upstream servers.

 

# By default, exchange time with everybody, but don't allow configuration.

restrict -4 default kod notrap nomodify nopeer noquery limited

restrict -6 default kod notrap nomodify nopeer noquery limited

 

# Local users may interrogate the ntp server more closely.

restrict 127.0.0.1

restrict ::1

 

#增加214作为时间服务器即可

server 192.168.0.214

# Needed for adding pool entries

restrict source notrap nomodify noquery

 

# Clients from this (example!) subnet have unlimited access, but only if

# cryptographically authenticated.

#restrict 192.168.123.0 mask 255.255.255.0 notrust

 

 

# If you want to provide time to your local subnet, change the next line.

# (Again, the address is an example only.)

#broadcast 192.168.123.255

 

# If you want to listen to time broadcasts on your local subnet, de-comment the

# next lines.  Please do this only if you trust everybody on the network!

#disable auth

#broadcastclient

 

#Changes recquired to use pps synchonisation as explained in documentation:

#http://www.ntp.org/ntpfaq/NTP-s-config-adv.htm#AEN3918

 

#server 127.127.8.1 mode 135 prefer    # Meinberg GPS167 with PPS

#fudge 127.127.8.1 time1 0.0042        # relative to PPS for my hardware

 

#server 127.127.22.1                   # ATOM(PPS)

#fudge 127.127.22.1 flag3 1            # enable PPS API

3. 修改完以后退出，重启ntp服务

$ sudo service ntp restart

三 链接服务器端与客户端

1. 首先在客户端使用ping命令查看能否连接到服务器端

$ ping 192.168.0.3（这里是服务器IP）

2. 如果能否ping通，首先在客户端上关闭ntp服务，然后测试一下手动同步能否成功

$ sudo /etc/init.d/ntp stop

$ ntpdate 192.169.……（ntp 服务器地址）

这里注意，每次手动同步之前都要先停止ntp服务，即以上两行指令必须成对输入，因为ntp服务一般会随机自动启动。。第一次对时可能误差较大，重复以上指令几次，直到命令行显示的差值接近0，即算完成同步

3. 如果手动同步测试成功，就可以进行自动同步的配置了。

方法一（不推荐）：如果etc目录下存在ntp.conf文件，输入指令$ sudo gedit /etc/ntp.conf，在文件中添加以下语句

server 192.168.……(ntp服务器地址)

保存并退出，电脑中会有一个进程自动去读取该配置文件，并跟随服务器间隔一定时间进行一次对时。具体间隔时间不可查，正常情况下服务器是一台工控机，属性由机器本身决定。

方法二（推荐，更新频率可选）如果etc目录下不存在ntp.conf文件，或者想自己决定同步的频率，可输入指令$ sudo gedit /etc/crontab，在最后一行文本，文本内容如下：

***** user command

第1个 * 表示分钟：取值范围为1～59，当需要一分钟执行一次时，可表示为 * /1,以下均同；
第2个 * 表示小时：取值范围0～23
第3个 * 表示日期：取值范围1～31
第4个 * 表示月份：取值范围1～12
第5个 * 表示星期：取值范围：0～6（0表示星期天）
user为需要执行该命令的用户，command表示要运行的命令

例如，我需要在root用户下一分钟自动对时一次，则命令为：

*/1 * * * * root ntpdate 192.168.……（ntp服务器地址）

保存退出，重启客户端即可。

四 其他（随时补充）

1. 如果想看一下连接情况，可以在服务器端或者客户端输入以下命令

$ sudo ntpq -p

该命令列出了所有作为时钟源校正过本地NTP服务器时钟上层NTP服务器的列表，详细解读 https://www.cnblogs.com/zxiaozhou/p/13355415.html

2. 几个ntp服务的相关命令

启动     $ sudo service ntpstart

停止     $ sudo service ntp stop

重新启动     $ sudo service ntprestart

 

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