先查看当前系统时间
root@ubuntu:~# date -R Thu, 14 Jan 2021 15:15:35 +0000
时区不对，需要修改时区
1.运行tzselect
root@ubuntu:~# tzselect Please identify a location so that time zone rules can be set correctly. Please select a continent, ocean, "coord", or "TZ". 1) Africa 2) Americas 3) Antarctica 4) Asia 5) Atlantic Ocean 6) Australia 7) Europe 8) Indian Ocean 9) Pacific Ocean 10) coord - I want to use geographical coordinates. 11) TZ - I want to specify the time zone using the Posix TZ format. #? 4 Please select a country whose clocks agree with yours. 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. Selected time is now: Thu Jan 14 23:15:45 CST 2021. Universal Time is now: Thu Jan 14 15:15:45 UTC 2021. 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
在这里我们选择亚洲 Asia，确认之后选择中国(China)，最后选择北京(Beijing)
2.复制文件到/etc目录下
root@ubuntu:~# cp /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
3.再次查看时间date -R，已经修改为北京时间
root@ubuntu:~# date -R Thu, 14 Jan 2021 23:16:18 +0800
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如果需要还可以直接改时间
date -s MM/DD/YY //修改日期 date -s hh:mm:ss //修改时间
在修改时间以后，修改硬件CMOS的时间
hwclock --systohc //非常重要，如果没有这一步的话，后面时间还是不准
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Ubuntu18.04之后的版本可以尝试下面的代码修改时区
timedatectl set-timezone Asia/Shanghai