Ntp

本来这篇文章是想讲puppet的，但是今天有两个同事不在，特别特别忙，在一个现在Puppet也不是特别火，做以决定以后有机会在总结吧，先总结下做puppet之前的时间同步吧

好久不用Ntp了发现自己全都忘了，知识这个东西不用就会忘，但是捡起来很容易

同步时间：

[root@linux-szge ~]# rpm -q ntp 
ntp-4.2.6p5-1.el6.centos.x86_64

ntpdate 192.168.1.185
20 Feb 01:19:33 ntpdate[23968]: no server suitable for synchronization found（同步失败，原因是我的185服务器上默认拒绝所有IP的时间同步）
在185机器ntp.conf上添加一行
restrict 192.168.0.0 mask 255.255.0.0 nomodify notrap

[root@linux-szge ~]# ntpdate 192.168.1.185 （再次同步，成功）
19 Feb 17:24:07 ntpdate[23991]: adjust time server 192.168.1.185 offset -0.000145 sec

但是发现时间好像不对啊，我擦，我185上的时间不是这个啊，于是查找原因
[root@linux-szge ~]# date
Sun Feb 19 17:24:15 PST 2017

尝试同步亚洲时间服务器，但是发现时间还是不对，这就断定了是我机器的配置问题了
[root@linux-szge ~]# /usr/sbin/ntpdate cn.pool.ntp.org
19 Feb 17:27:24 ntpdate[23999]: adjust time server 115.28.122.198 offset 0.039672 sec

[root@linux-szge ~]# date
Sun Feb 19 17:28:50 PST 2017
[root@linux-szge ~]# /usr/sbin/ntpdate cn.pool.ntp.org
19 Feb 17:28:56 ntpdate[24023]: adjust time server 52.187.51.163 offset -0.006311 sec
[root@linux-szge ~]# date 
Sun Feb 19 17:29:00 PST 2017

手动修改时区
[root@linux-szge ~]# tzselect 
Please identify a location so that time zone rules can be set correctly.
Please select a continent or ocean.
 1) Africa
 2) Americas
 3) Antarctica
 4) Arctic Ocean
 5) Asia
 6) Atlantic Ocean
 7) Australia
 8) Europe
 9) Indian Ocean
10) Pacific Ocean
11) none - I want to specify the time zone using the Posix TZ format.
#? 5
Please select a country.
 1) Afghanistan           18) Israel                35) Palestine
 2) Armenia               19) Japan                 36) Philippines
 3) Azerbaijan            20) Jordan                37) Qatar
 4) Bahrain               21) Kazakhstan            38) Russia
 5) Bangladesh            22) Korea (North)         39) Saudi Arabia
 6) Bhutan                23) Korea (South)         40) Singapore
 7) Brunei                24) Kuwait                41) Sri Lanka
 8) Cambodia              25) Kyrgyzstan            42) Syria
 9) China                 26) Laos                  43) Taiwan
10) Cyprus                27) Lebanon               44) Tajikistan
11) East Timor            28) Macau                 45) Thailand
12) Georgia               29) Malaysia              46) Turkmenistan
13) Hong Kong             30) Mongolia              47) United Arab Emirates
14) India                 31) Myanmar (Burma)       48) Uzbekistan
15) Indonesia             32) Nepal                 49) Vietnam
16) Iran                  33) Oman                  50) Yemen
17) Iraq                  34) Pakistan
#? 9
Please select one of the following time zone regions.
1) Beijing Time
2) Xinjiang Time
#? 1

The following information has been given:

        China
        Beijing Time

Therefore TZ='Asia/Shanghai' will be used.
Local time is now:      Mon Feb 20 09:34:38 CST 2017.
Universal Time is now:  Mon Feb 20 01:34:38 UTC 2017.
Is the above information OK?
1) Yes
2) No
#? 1

You can make this change permanent for yourself by appending the line
        TZ='Asia/Shanghai'; export TZ
to the file '.profile' in your home directory; then log out and log in again.

Here is that TZ value again, this time on standard output so that you
can use the /usr/bin/tzselect command in shell scripts:
Asia/Shanghai

修改完时区发现时间还不对，我就迷茫了，但是发现上面有一行提示
[root@linux-szge ~]# date
 Sun Feb 19 17:29:00 PST 2017
You can make this change permanent for yourself by appending the line
        TZ='Asia/Shanghai'; export TZ
to the file '.profile' in your home directory; then log out and log in again.

尝试一下，输入命令，切换下，成功
[root@linux-szge ~]# TZ='Asia/Shanghai'; export TZ 
[root@linux-szge ~]# su
[root@linux-szge ~]# date 
Mon Feb 20 09:29:26 CST 2017