linux時區和時間設定
1，修改時區
調整時區使用tzselect
[root@lyn ~]# hwclock
Tue 13 Nov 2018 11:52:26 PM AST -0.198205 seconds
[root@lyn ~]# 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) east China - Beijing, Guangdong, Shanghai, etc.
2) Heilongjiang (except Mohe), Jilin
3) central China - Sichuan, Yunnan, Guangxi, Shaanxi, Guizhou, etc.
4) most of Tibet & Xinjiang
5) west Tibet & Xinjiang
#? 1
The following information has been given:
China
east China - Beijing, Guangdong, Shanghai, etc.
Therefore TZ='Asia/Shanghai' will be used.
Local time is now: Wed Nov 14 11:52:47 CST 2018.
Universal Time is now: Wed Nov 14 03:52:47 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
注：修改profile檔案，新增以下兩行：
TZ='Asia/Shanghai'
export TZ
[root@lyn ~]# vim /etc/profile
[root@lyn ~]# source /etc/profile
[root@lyn ~]# date
Wed Nov 14 11:56:16 CST 2018
由此發現，時區由AST 變成了CST。CST ：中國標準時間
2，修改時間
注：linux系統啟動時，系統時間同步硬體時間，如果只修改系統時間，重啟後系統時間就會變成硬體時間。
例如，現在要求設定系統時間為2018-11-14 10:45:35
1，使用date檢視系統時間。
[root@lyn ~]# date
Wed Nov 14 18:29:43 CST 2018
2，檢視硬體時間，使用命令hwclock。
[root@lyn ~]# hwclock
Wed 14 Nov 2018 06:29:41 PM CST -0.557725 seconds
3，調整時間為要求的時間。
方法一：先設定系統時間，再根據系統時間同步硬體時間。
[root@lyn ~]# date -s 11/14/2018
Wed Nov 14 00:00:00 CST 2018
[root@lyn ~]# date -s 10:48:50
Wed Nov 14 10:48:50 CST 2018
[root@lyn ~]# hwclock --systohc ##使用系統時間同步硬體時間
[root@lyn ~]# hwclock
Wed 14 Nov 2018 10:49:33 AM CST -0.756860 seconds
方法二：先設定硬體時間，再根據硬體時間同步系統時間，或者重啟系統。
[root@lyn ~]# hwclock --set --date="11/14/2018 10:56:35"
[root@lyn ~]# hwclock
Wed 14 Nov 2018 10:56:44 AM CST -0.709765 seconds
[root@lyn ~]# hwclock --hctosys ##使用硬體時間同步系統時間
[root@lyn ~]# date
Wed Nov 14 10:57:11 CST 2018