root@focal2-2:~# ntpdate ntp1.aliyun.com 27 Jul 06:03:10 ntpdate[7293]: adjust time server 120.25.115.20 offset 0.000071 sec root@focal2-2:~# date Mon Jul 27 06:03:32 UTC 2020 root@focal2-2:~# date -R Mon, 27 Jul 2020 06:04:17 +0000 root@focal2-2:~# 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 timezone using the Posix TZ format. #? 5 Please select a country whose clocks agree with yours. 1) Bermuda 2) Cape Verde 3) Falkland Islands 4) Faroe Islands 5) Iceland 6) Portugal 7) South Georgia & the South Sandwich Islands 8) Spain #? quit Please enter a number in range. #? q Please enter a number in range. #? b Please enter a number in range. #? ^C root@focal2-2:~# date -R Mon, 27 Jul 2020 06:05:15 +0000 root@focal2-2:~# 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 timezone 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 timezones. 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: Mon Jul 27 14:05:47 CST 2020. Universal Time is now: Mon Jul 27 06:05:47 UTC 2020. Is the above information OK? 1) Yes 2) No #? yes Please enter a number in range. #? 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@focal2-2:~# date -R Mon, 27 Jul 2020 06:06:39 +0000 root@focal2-2:~# date Mon Jul 27 06:06:46 UTC 2020 root@focal2-2:~# ntpdate cn.pool.ntp.org 27 Jul 06:08:18 ntpdate[7348]: adjust time server 193.182.111.14 offset -0.011013 sec root@focal2-2:~# date Mon Jul 27 06:08:26 UTC 2020 root@focal2-2:~# hwclock --systohc root@focal2-2:~# date Mon Jul 27 06:09:03 UTC 2020 root@focal2-2:~# ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime root@focal2-2:~# date Mon Jul 27 14:09:33 CST 2020 root@focal2-2:~#
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@focal:/etc/frr# date Mon Jul 27 06:11:29 UTC 2020 root@focal:/etc/frr# ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime root@focal:/etc/frr# date Mon Jul 27 14:11:41 CST 2020 root@focal:/etc/frr#