GNU/Linux - 时区设置

CST = China Standard Time = 北京时间/中国标准时间 = 在时区划分上，属东八区，比协调世界时早 8 小时，记为 UTC+8 

GMT = Greenwich Mean Time = 格林威治标准时间 = 是指位于英国伦敦郊区的格林尼治天文台的标准时间，因为本初子午线被定义在通过那里的经线 

UTC = Universal Time Coordinated = 协调世界时 

DST = Daylight Saving Time = 夏令时 = 一个地区的标准时间，即在夏令时 (DST, Daylight Saving Time) 时期以外使用的当地时间。全球 60% 以上的国家全年都只使用标准时间。而剩下的那些国家则在夏季使用夏令时，通常是把时钟从标准时间向前调 1 小时。

EST = Eastern Standard Time, 表示DST没有激活。

使用date命令显示当前日期和时间时，将显示为系统配置的时区的时间，包括处理 DST（如果该时区适用）。

该命令将输出当前日期和时间，如果系统时区设置在遵守 DST 的地区，则将根据 DST 进行调整。

使用date命令设置系统时间时，通常使用当地时间（包括任何 DST 调整）。

sudo date -s "2024-05-22 12:34:56"

该命令将系统时间设置为指定的日期和时间。输入的时间应为当地时区的时间，包括 DST（如果适用）。

系统的时区配置决定了是否应用 DST 以及本地时间的显示方式。该配置通常使用 /etc/localtime 文件设置，该文件是 /usr/share/zoneinfo 中时区数据文件的符号链接。

$ ls /etc/localtime  -l

lrwxrwxrwx 1 root root 33  3月  6 09:03 /etc/localtime -> /usr/share/zoneinfo/Asia/Shanghai

查看当前时区配置：

$ timedatectl

               Local time: 三 2024-05-22 17:58:46 CST

           Universal time: 三 2024-05-22 09:58:46 UTC

                 RTC time: 三 2024-05-22 09:58:45

                Time zone: Asia/Shanghai (CST, +0800)

System clock synchronized: no

              NTP service: active

          RTC in local TZ: no

$ date

2024年 05月 22日 星期三 17:52:12 CST

该命令提供有关系统时区的详细信息，包括 DST 是否激活。

更改系统时区：

$ sudo timedatectl set-timezone America/New_York

$ timedatectl

               Local time: 五 2027-07-23 16:07:39 EDT

           Universal time: 五 2027-07-23 20:07:39 UTC

                 RTC time: 三 2024-05-22 10:21:42

                Time zone: America/New_York (EDT, -0400)

System clock synchronized: no

              NTP service: active

          RTC in local TZ: no

$ date

2027年 07月 23日 星期五 16:08:31 EDT

Override a Time Zone / 查询不同时区的日期

默认情况下，date 命令使用 /etc/localtime 中定义的时区。要在环境中使用不同的时区，请将 TZ 变量设置为所需的时区。

By default, the date command uses the time zone defined in /etc/localtime. To use a different time zone in the environment, set the TZ variable to the desired time zone.

$ TZ='America/New_York' date

日期命令还可以显示不同时区的当地时间。例如，要显示澳大利亚东海岸下周一下午 4:30 时，本系统时区的当地时间，请键入：

The date command can also show the local time for a different time zone. For example, to display the local time for 4:30 PM next Monday on the Australian east coast, type:

date -d 'TZ="Australia/Sydney" 04:30 next Monday'

要查看所有可用时区，请使用 timedatectl list-timezones 命令。

To see all available time zones, use the timedatectl list-timezones command.

$ timedatectl  list-timezones

Africa/Abidjan

Africa/Accra

Africa/Addis_Ababa

Africa/Algiers

Africa/Asmara

Africa/Asmera

Africa/Bamako

Africa/Bangui

Africa/Banjul

Africa/Bissau

Africa/Blantyre

Africa/Brazzaville

Africa/Bujumbura

Africa/Cairo

Africa/Casablanca

Africa/Ceuta

Africa/Conakry

Africa/Dakar

Africa/Dar_es_Salaam

Africa/Djibouti

Africa/Douala

Africa/El_Aaiun

Africa/Freetown

Africa/Gaborone

Africa/Harare

Africa/Johannesburg

Africa/Juba

Africa/Kampala

Africa/Khartoum

Africa/Kigali

Africa/Kinshasa

Africa/Lagos

Africa/Libreville

Africa/Lome

Africa/Luanda

Africa/Lubumbashi

Africa/Lusaka

Africa/Malabo

Africa/Maputo

Africa/Maseru

Africa/Mbabane

Africa/Mogadishu

Africa/Monrovia

Africa/Nairobi

Africa/Ndjamena

Africa/Niamey

Africa/Nouakchott

Africa/Ouagadougou

Africa/Porto-Novo

Africa/Sao_Tome

Africa/Timbuktu

Africa/Tripoli

Africa/Tunis

Africa/Windhoek

America/Adak

America/Anchorage

America/Anguilla

America/Antigua

America/Araguaina

America/Argentina/Buenos_Aires

America/Argentina/Catamarca

America/Argentina/ComodRivadavia

America/Argentina/Cordoba

America/Argentina/Jujuy

America/Argentina/La_Rioja

America/Argentina/Mendoza

America/Argentina/Rio_Gallegos

America/Argentina/Salta

America/Argentina/San_Juan

America/Argentina/San_Luis

America/Argentina/Tucuman

America/Argentina/Ushuaia

America/Aruba

America/Asuncion

America/Atikokan

America/Atka

America/Bahia

America/Bahia_Banderas

America/Barbados

America/Belem

America/Belize

America/Blanc-Sablon

America/Boa_Vista

America/Bogota

America/Boise

America/Buenos_Aires

America/Cambridge_Bay

America/Campo_Grande

America/Cancun

America/Caracas

America/Catamarca

America/Cayenne

America/Cayman

America/Chicago

America/Chihuahua

America/Ciudad_Juarez

America/Coral_Harbour

America/Cordoba

America/Costa_Rica

America/Creston

America/Cuiaba

America/Curacao

America/Danmarkshavn

America/Dawson

America/Dawson_Creek

America/Denver

America/Detroit

America/Dominica

America/Edmonton

America/Eirunepe

America/El_Salvador

America/Ensenada

America/Fort_Nelson

America/Fort_Wayne

America/Fortaleza

America/Glace_Bay

America/Godthab

America/Goose_Bay

America/Grand_Turk

America/Grenada

America/Guadeloupe

America/Guatemala

America/Guayaquil

America/Guyana

America/Halifax

America/Havana

America/Hermosillo

America/Indiana/Indianapolis

America/Indiana/Knox

America/Indiana/Marengo

America/Indiana/Petersburg

America/Indiana/Tell_City

America/Indiana/Vevay

America/Indiana/Vincennes

America/Indiana/Winamac

America/Indianapolis

America/Inuvik

America/Iqaluit

America/Jamaica

America/Jujuy

America/Juneau

America/Kentucky/Louisville

America/Kentucky/Monticello

America/Knox_IN

America/Kralendijk

America/La_Paz

America/Lima

America/Los_Angeles

America/Louisville

America/Lower_Princes

America/Maceio

America/Managua

America/Manaus

America/Marigot

America/Martinique

America/Matamoros

America/Mazatlan

America/Mendoza

America/Menominee

America/Merida

America/Metlakatla

America/Mexico_City

America/Miquelon

America/Moncton

America/Monterrey

America/Montevideo

America/Montreal

America/Montserrat

America/Nassau

America/New_York

America/Nipigon

America/Nome

America/Noronha

America/North_Dakota/Beulah

America/North_Dakota/Center

America/North_Dakota/New_Salem

America/Nuuk

America/Ojinaga

America/Panama

America/Pangnirtung

America/Paramaribo

America/Phoenix

America/Port-au-Prince

America/Port_of_Spain

America/Porto_Acre

America/Porto_Velho

America/Puerto_Rico

America/Punta_Arenas

America/Rainy_River

America/Rankin_Inlet

America/Recife

America/Regina

America/Resolute

America/Rio_Branco

America/Rosario

America/Santa_Isabel

America/Santarem

America/Santiago

America/Santo_Domingo

America/Sao_Paulo

America/Scoresbysund

America/Shiprock

America/Sitka

America/St_Barthelemy

America/St_Johns

America/St_Kitts

America/St_Lucia

America/St_Thomas

America/St_Vincent

America/Swift_Current

America/Tegucigalpa

America/Thule

America/Thunder_Bay

America/Tijuana

America/Toronto

America/Tortola

America/Vancouver

America/Virgin

America/Whitehorse

America/Winnipeg

America/Yakutat

America/Yellowknife

Antarctica/Casey

Antarctica/Davis

Antarctica/DumontDUrville

Antarctica/Macquarie

Antarctica/Mawson

Antarctica/McMurdo

Antarctica/Palmer

Antarctica/Rothera

Antarctica/South_Pole

Antarctica/Syowa

Antarctica/Troll

Antarctica/Vostok

Arctic/Longyearbyen

Asia/Aden

Asia/Almaty

Asia/Amman

Asia/Anadyr

Asia/Aqtau

Asia/Aqtobe

Asia/Ashgabat

Asia/Ashkhabad

Asia/Atyrau

Asia/Baghdad

Asia/Bahrain

Asia/Baku

Asia/Bangkok

Asia/Barnaul

Asia/Beirut

Asia/Bishkek

Asia/Brunei

Asia/Calcutta

Asia/Chita

Asia/Choibalsan

Asia/Chongqing

Asia/Chungking

Asia/Colombo

Asia/Dacca

Asia/Damascus

Asia/Dhaka

Asia/Dili

Asia/Dubai

Asia/Dushanbe

Asia/Famagusta

Asia/Gaza

Asia/Harbin

Asia/Hebron

Asia/Ho_Chi_Minh

Asia/Hong_Kong

Asia/Hovd

Asia/Irkutsk

Asia/Istanbul

Asia/Jakarta

Asia/Jayapura

Asia/Jerusalem

Asia/Kabul

Asia/Kamchatka

Asia/Karachi

Asia/Kashgar

Asia/Kathmandu

Asia/Katmandu

Asia/Khandyga

Asia/Kolkata

Asia/Krasnoyarsk

Asia/Kuala_Lumpur

Asia/Kuching

Asia/Kuwait

Asia/Macao

Asia/Macau

Asia/Magadan

Asia/Makassar

Asia/Manila

Asia/Muscat

Asia/Nicosia

Asia/Novokuznetsk

Asia/Novosibirsk

Asia/Omsk

Asia/Oral

Asia/Phnom_Penh

Asia/Pontianak

Asia/Pyongyang

Asia/Qatar

Asia/Qostanay

Asia/Qyzylorda

Asia/Rangoon

Asia/Riyadh

Asia/Saigon

Asia/Sakhalin

Asia/Samarkand

Asia/Seoul

Asia/Shanghai

Asia/Singapore

Asia/Srednekolymsk

Asia/Taipei

Asia/Tashkent

Asia/Tbilisi

Asia/Tehran

Asia/Tel_Aviv

Asia/Thimbu

Asia/Thimphu

Asia/Tokyo

Asia/Tomsk

Asia/Ujung_Pandang

Asia/Ulaanbaatar

Asia/Ulan_Bator

Asia/Urumqi

Asia/Ust-Nera

Asia/Vientiane

Asia/Vladivostok

Asia/Yakutsk

Asia/Yangon

Asia/Yekaterinburg

Asia/Yerevan

Atlantic/Azores

Atlantic/Bermuda

Atlantic/Canary

Atlantic/Cape_Verde

Atlantic/Faeroe

Atlantic/Faroe

Atlantic/Jan_Mayen

Atlantic/Madeira

Atlantic/Reykjavik

Atlantic/South_Georgia

Atlantic/St_Helena

Atlantic/Stanley

Australia/ACT

Australia/Adelaide

Australia/Brisbane

Australia/Broken_Hill

Australia/Canberra

Australia/Currie

Australia/Darwin

Australia/Eucla

Australia/Hobart

Australia/LHI

Australia/Lindeman

Australia/Lord_Howe

Australia/Melbourne

Australia/NSW

Australia/North

Australia/Perth

Australia/Queensland

Australia/South

Australia/Sydney

Australia/Tasmania

Australia/Victoria

Australia/West

Australia/Yancowinna

Brazil/Acre

Brazil/DeNoronha

Brazil/East

Brazil/West

CET

CST6CDT

Canada/Atlantic

Canada/Central

Canada/Eastern

Canada/Mountain

Canada/Newfoundland

Canada/Pacific

Canada/Saskatchewan

Canada/Yukon

Chile/Continental

Chile/EasterIsland

Cuba

EET

EST

EST5EDT

Egypt

Eire

Etc/GMT

Etc/GMT+0

Etc/GMT+1

Etc/GMT+10

Etc/GMT+11

Etc/GMT+12

Etc/GMT+2

Etc/GMT+3

Etc/GMT+4

Etc/GMT+5

Etc/GMT+6

Etc/GMT+7

Etc/GMT+8

Etc/GMT+9

Etc/GMT-0

Etc/GMT-1

Etc/GMT-10

Etc/GMT-11

Etc/GMT-12

Etc/GMT-13

Etc/GMT-14

Etc/GMT-2

Etc/GMT-3

Etc/GMT-4

Etc/GMT-5

Etc/GMT-6

Etc/GMT-7

Etc/GMT-8

Etc/GMT-9

Etc/GMT0

Etc/Greenwich

Etc/UCT

Etc/UTC

Etc/Universal

Etc/Zulu

Europe/Amsterdam

Europe/Andorra

Europe/Astrakhan

Europe/Athens

Europe/Belfast

Europe/Belgrade

Europe/Berlin

Europe/Bratislava

Europe/Brussels

Europe/Bucharest

Europe/Budapest

Europe/Busingen

Europe/Chisinau

Europe/Copenhagen

Europe/Dublin

Europe/Gibraltar

Europe/Guernsey

Europe/Helsinki

Europe/Isle_of_Man

Europe/Istanbul

Europe/Jersey

Europe/Kaliningrad

Europe/Kiev

Europe/Kirov

Europe/Kyiv

Europe/Lisbon

Europe/Ljubljana

Europe/London

Europe/Luxembourg

Europe/Madrid

Europe/Malta

Europe/Mariehamn

Europe/Minsk

Europe/Monaco

Europe/Moscow

Europe/Nicosia

Europe/Oslo

Europe/Paris

Europe/Podgorica

Europe/Prague

Europe/Riga

Europe/Rome

Europe/Samara

Europe/San_Marino

Europe/Sarajevo

Europe/Saratov

Europe/Simferopol

Europe/Skopje

Europe/Sofia

Europe/Stockholm

Europe/Tallinn

Europe/Tirane

Europe/Tiraspol

Europe/Ulyanovsk

Europe/Uzhgorod

Europe/Vaduz

Europe/Vatican

Europe/Vienna

Europe/Vilnius

Europe/Volgograd

Europe/Warsaw

Europe/Zagreb

Europe/Zaporozhye

Europe/Zurich

Factory

GB

GB-Eire

GMT

GMT+0

GMT-0

GMT0

Greenwich

HST

Hongkong

Iceland

Indian/Antananarivo

Indian/Chagos

Indian/Christmas

Indian/Cocos

Indian/Comoro

Indian/Kerguelen

Indian/Mahe

Indian/Maldives

Indian/Mauritius

Indian/Mayotte

Indian/Reunion

Iran

Israel

Jamaica

Japan

Kwajalein

Libya

MET

MST

MST7MDT

Mexico/BajaNorte

Mexico/BajaSur

Mexico/General

NZ

NZ-CHAT

Navajo

PRC

PST8PDT

Pacific/Apia

Pacific/Auckland

Pacific/Bougainville

Pacific/Chatham

Pacific/Chuuk

Pacific/Easter

Pacific/Efate

Pacific/Enderbury

Pacific/Fakaofo

Pacific/Fiji

Pacific/Funafuti

Pacific/Galapagos

Pacific/Gambier

Pacific/Guadalcanal

Pacific/Guam

Pacific/Honolulu

Pacific/Johnston

Pacific/Kanton

Pacific/Kiritimati

Pacific/Kosrae

Pacific/Kwajalein

Pacific/Majuro

Pacific/Marquesas

Pacific/Midway

Pacific/Nauru

Pacific/Niue

Pacific/Norfolk

Pacific/Noumea

Pacific/Pago_Pago

Pacific/Palau

Pacific/Pitcairn

Pacific/Pohnpei

Pacific/Ponape

Pacific/Port_Moresby

Pacific/Rarotonga

Pacific/Saipan

Pacific/Samoa

Pacific/Tahiti

Pacific/Tarawa

Pacific/Tongatapu

Pacific/Truk

Pacific/Wake

Pacific/Wallis

Pacific/Yap

Poland

Portugal

ROC

ROK

Singapore

Turkey

UCT

US/Alaska

US/Aleutian

US/Arizona

US/Central

US/East-Indiana

US/Eastern

US/Hawaii

US/Indiana-Starke

US/Michigan

US/Mountain

US/Pacific

US/Samoa

UTC

Universal

W-SU

WET

Zulu