一、使用 NTP 服務時間同步

安裝 ntp

[root@node?~]#?yum?-y?install?ntp

啟動 ntp 服務

[root@node?~]#?systemctl?start??ntpd
[root@node?~]#?systemctl?enable??ntpd
Created?symlink?from?/etc/systemd/system/multi-user.target.wants/ntpd.service?to?/usr/lib/systemd/system/ntpd.service.

查看 ntp 服務

[root@node?~]#?systemctl?status?ntpd
●?ntpd.service?-?Network?Time?Service
???Loaded:?loaded?(/usr/lib/systemd/system/ntpd.service;?enabled;?vendor?preset:?disabled)
???Active:?active?(running)?since?Thu?2022-08-04?0847?CST;?7h?left
?Main?PID:?20746?(ntpd)
????Tasks:?1
???Memory:?768.0K
???CGroup:?/system.slice/ntpd.service
???????????└─20746?/usr/sbin/ntpd?-u?ntp:ntp?-g

Aug?04?0847?node?ntpd[20746]:?Listen?normally?on?6?lo?::1?UDP?123
Aug?04?0847?node?ntpd[20746]:?Listen?normally?on?7?ens33?fe80:72979934?UDP?123
Aug?04?0847?node?ntpd[20746]:?Listening?on?routing?socket?on?fd?#24?for?interface?updates
Aug?04?0847?node?systemd[1]:?Started?Network?Time?Service.
Aug?04?0847?node?ntpd[20746]:?0.0.0.0?c016?06?restart
Aug?04?0847?node?ntpd[20746]:?0.0.0.0?c012?02?freq_set?kernel?0.000?PPM
Aug?04?0847?node?ntpd[20746]:?0.0.0.0?c011?01?freq_not_set
Aug?04?0856?node?ntpd[20746]:?0.0.0.0?c61c?0c?clock_step?-28798.353463?s
Aug?04?0057?node?ntpd[20746]:?0.0.0.0?c614?04?freq_mode
Aug?04?0058?node?ntpd[20746]:?0.0.0.0?c618?08?no_sys_peer

修改 ntp.conf 文件

[root@node?~]#?vim?/etc/ntp.conf
[root@node?~]#?grep?server?/etc/ntp.conf?
#?Use?public?servers?from?the?pool.ntp.org?project.
#server?0.centos.pool.ntp.org?iburst
server?ntp.aliyun.com?iburst
#broadcast?192.168.1.255?autokey?#?broadcast?server
#broadcast?224.0.1.1?autokey??#?multicast?server
#manycastserver?239.255.254.254??#?manycast?server

重啟服務

[root@node?~]#?systemctl?restart?ntpd

檢查同步狀態

[root@node?~]#?ntpq?-p
?????remote???????????refid??????st?t?when?poll?reach???delay???offset??jitter
==============================================================================
?203.107.6.88????100.107.25.114???2?u????2???64????1???30.975??149.499???0.393

二、使用 ntpdate 同步

使用 ntpd 命令同步

[root@node?~]#?ntpdate?ntp.aliyun.com
?4?Aug?0017?ntpdate[20924]:?adjust?time?server?203.107.6.88?offset?-0.001543?sec

查看時間

[root@node?~]#?date
Thu?Aug??4?0046?CST?2022

三、處理 ntpdate 同步失敗報錯處理方法

報錯信息

cna02:~?#?ntpdate?ntp1.aliyun.com
?4?Aug?0741?ntpdate[18694]:?the?NTP?socket?is?in?use,?exiting

處理方法

cna02:~?#?service?ntpd?stop
Redirecting?to?/bin/systemctl?stop?ntpd.service

重新同步

cna02:~?#?ntpdate?ntp1.aliyun.com
?3?Aug?2336?ntpdate[28980]:?step?time?server?120.25.115.20?offset?-28911.609110?sec

查看時間是否正確

cna02:~?#?date
Wed?Aug??3?2341?CST?2022

四、使用 chrony 服務時間同步

安裝 chrony

[root@node?~]#?yum?-y?install?chrony
Loaded?plugins:?fastestmirror,?langpacks
Loading?mirror?speeds?from?cached?hostfile
?*?base:?mirrors.bfsu.edu.cn
?*?extras:?mirrors.bfsu.edu.cn
?*?updates:?mirrors.bfsu.edu.cn
Resolving?Dependencies
-->?Running?transaction?check
--->?Package?chrony.x86_64?0:3.2-2.el7?will?be?updated
--->?Package?chrony.x86_64?0:3.4-1.el7?will?be?an?update
-->?Finished?Dependency?Resolution

Dependencies?Resolved

===============================================================================================================================================================================
?Package??????????????????????????????????Arch?????????????????????????????????????Version????????????????????????????????????????Repository??????????????????????????????Size
===============================================================================================================================================================================
Updating:
?chrony???????????????????????????????????x86_64???????????????????????????????????3.4-1.el7??????????????????????????????????????base???????????????????????????????????251?k

Transaction?Summary
===============================================================================================================================================================================
Upgrade??1?Package

Total?download?size:?251?k
Downloading?packages:
No?Presto?metadata?available?for?base
chrony-3.4-1.el7.x86_64.rpm?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????|?251?kB??0000?????
Running?transaction?check
Running?transaction?test
Transaction?test?succeeded
Running?transaction
??Updating???:?chrony-3.4-1.el7.x86_64?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????1/2?
??Cleanup????:?chrony-3.2-2.el7.x86_64?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????2/2?
??Verifying??:?chrony-3.4-1.el7.x86_64?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????1/2?
??Verifying??:?chrony-3.2-2.el7.x86_64?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????2/2?

Updated:
??chrony.x86_64?0:3.4-1.el7????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????

Complete!

啟動 chrony 服務

[root@node?~]#?systemctl?enable?--now?chronyd
Created?symlink?from?/etc/systemd/system/multi-user.target.wants/chronyd.service?to?/usr/lib/systemd/system/chronyd.service.

查看 chrony 狀態

[root@node?~]#?systemctl?status?chronyd
●?chronyd.service?-?NTP?client/server
???Loaded:?loaded?(/usr/lib/systemd/system/chronyd.service;?enabled;?vendor?preset:?enabled)
???Active:?active?(running)?since?Thu?2022-08-04?0027?CST;?29s?ago
?????Docs:?man:chronyd(8)
???????????man:chrony.conf(5)
??Process:?21136?ExecStartPost=/usr/libexec/chrony-helper?update-daemon?(code=exited,?status=0/SUCCESS)
??Process:?21132?ExecStart=/usr/sbin/chronyd?$OPTIONS?(code=exited,?status=0/SUCCESS)
?Main?PID:?21134?(chronyd)
????Tasks:?1
???Memory:?364.0K
???CGroup:?/system.slice/chronyd.service
???????????└─21134?/usr/sbin/chronyd

Aug?04?0027?node?systemd[1]:?Starting?NTP?client/server...
Aug?04?0027?node?chronyd[21134]:?chronyd?version?3.4?starting?(+CMDMON?+NTP?+REFCLOCK?+RTC?+PRIVDROP?+SCFILTER?+SIGND?+ASYNCDNS?+SECHASH?+IPV6?+DEBUG)
Aug?04?0027?node?systemd[1]:?Started?NTP?client/server.
Aug?04?0035?node?chronyd[21134]:?Selected?source?193.182.111.141
Aug?04?0035?node?chronyd[21134]:?Source?78.46.102.180?replaced?with?94.237.64.20

修改配置文件

[root@node?~]#?grep?server?/etc/chrony.conf?
#?Use?public?servers?from?the?pool.ntp.org?project.
#server?0.centos.pool.ntp.org?iburst
#server?1.centos.pool.ntp.org?iburst
#server?3.centos.pool.ntp.org?iburst
server?ntp1.aliyun.com?iburst

重啟服務

[root@node?~]#?systemctl?restart?chronyd

檢查時間同步狀態

[root@node?~]#?chronyc?sources
210?Number?of?sources?=?1
MS?Name/IP?address?????????Stratum?Poll?Reach?LastRx?Last?sample???????????????
===============================================================================
^*?120.25.115.20?????????????????2???6????71????26???+751us[+1549us]?+/-???19ms

五、手動修改時間

修改時間方法 1

[root@node?~]#?date?-s?"2012-05-23?0101"
Wed?May?23?0101?CST?2012
[root@node?~]#?date
Wed?May?23?0105?CST?2012

修改時間方法 2

修改時間順序為月日時分年. 秒

[root@tianyi?~]#?date?090621282021.28
Mon?Sep??6?2128?CST?2021

硬件時間向系統時間同步

[root@node?~]#?hwclock?-w

按格式輸出時間

[root@node?~]#?date?"+%Y-%m-%d?%H:%M:%S"
2012-05-23?0110

設置時區

[root@tianyi?backups]#?timedatectl?list-timezones?|grep?Shanghai
Asia/Shanghai
[root@tianyi?backups]#?timedatectl?set-timezone?Asia/Shanghai

?

?

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