一、背景:设置系统的时候选择市区明明是中国上海,但是后来用date命令查看时间时,时间又不对了。
相关词语解释
系统时间(System Clock):是指当前Linux Kernel中的时钟。
硬件时间(Real Time Clock,简称RTC):主板上由电池供电的时钟,这个硬件时钟可以在BIOS中进行设置。
当Linux启动时,硬件时钟会去读取系统时钟的设置,然后系统时钟就会独立于硬件运作。Linux中的所有命令(包括函数)都是采用的系统时钟设置。
出现上述问题的原因是有时候硬件时间和系统时间不同步。
解决方法:
[root@myp ~]# 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: Tue Oct 9 09:21:45 CST 2018.
Universal Time is now: Tue Oct 9 01:21:45 UTC 2018.
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
[root@myp ~]# TZ='Asia/Shanghai'; export TZ
[root@myp ~]# TZ='Asia/Shanghai'; export TZ
[root@myp ~]# vim .p
.pki/ .pulse/ .pulse-cookie
[root@myp ~]# vim .p
.pki/ .pulse/ .pulse-cookie
[root@myp ~]# vim .profile