Ubuntu 시간 관련 명령 사용하기

현재시간

root@NanoPC-T3:/home/pi# date
Wed Oct 12 11:35:01 UTC 2022

시간 변경

-10월12일20시37분2022년.30초

root@NanoPC-T3:/home/pi# sudo date 1012203722.30
Wed Oct 12 20:37:30 UTC 2022

date로 시간 변경시 재부팅 할때 시간이 적용 안되어있는경우가 있다.

커널시간과 메인보드 시간을 맞추자 => 하드웨어 클럭 쓰기를 실행해야 함

 

하드웨어 클럭 읽기

root@NanoPC-T3:/home/pi# hwclock -r
Tue Nov  8 22:43:01 2022  .025680 seconds

하드웨어 클럭 쓰기

root@NanoPC-T3:/home/pi# hwclock -w

NTP관련 명령

root@NanoPC-T3:/home/pi# ntpdate time.bora.net
12 Oct 11:27:23 ntpdate[3375]: adjust time server 203.248.240.140 offset 0.002434 sec

 

아래와 같이 NTP서버 동기화 업데이트가 안될 시

root@NanoPC-T3:/home/pi# ntpdate time.bora.net
12 Oct 11:25:29 ntpdate[3269]: the NTP socket is in use, exiting

 

1. NTP 서비스 중단

root@NanoPC-T3:/home/pi# /etc/init.d/ntp stop
[ ok ] Stopping ntp (via systemctl): ntp.service.

2. NTP 서버 동기화

root@NanoPC-T3:/home/pi# ntpdate time.bora.net
12 Oct 11:27:23 ntpdate[3375]: adjust time server 203.248.240.140 offset 0.002434 sec

3. NTP 서비스 재개

root@NanoPC-T3:/home/pi# /etc/init.d/ntp start
[ ok ] Starting ntp (via systemctl): ntp.service.

 

 

참고

-UTC시간 KST 시간대로 변경

root@NanoPC-T3:/home/pi# date
Wed Oct 12 11:45:48 UTC 2022
root@NanoPC-T3:/home/pi# ln -sf /usr/share/zoneinfo/Asia/Seoul /etc/localtime
root@NanoPC-T3:/home/pi# date
Wed Oct 12 20:46:18 KST 2022

-표현식에 따른 시간출력

root@NanoPC-T3:/home/pi#  date "+%Y-%m-%d %H:%M:%S"
2022-10-12 20:47:23

 

-NTP서버와의 시간차이

root@NanoPC-T3:/home/pi# ntpdate -d time.bora.net
12 Oct 11:28:37 ntpdate[3505]: ntpdate 4.2.8p4@1.3265-o Fri Jul  6 20:09:00 UTC 2018 (1)
Looking for host time.bora.net and service ntp
"주소정보" reversed to time.bora.net
host found : time.bora.net
transmit("주소정보")
receive("주소정보")
transmit("주소정보")
receive("주소정보")
transmit("주소정보")
receive("주소정보")
transmit("주소정보")
receive("주소정보")
server "주소정보", port 123
stratum 3, precision -16, leap 00, trust 000
refid ["주소정보"], delay 0.03305, dispersion 0.00021
transmitted 4, in filter 4
reference time:    e6f1233a.45819000  Wed, Oct 12 2022 11:27:54.271
originate timestamp: e6f1236b.694bc000  Wed, Oct 12 2022 11:28:43.411
transmit timestamp:  e6f1236b.68981496  Wed, Oct 12 2022 11:28:43.408
filter delay:  0.03305  0.03339  0.03307  0.03345
         0.00000  0.00000  0.00000  0.00000
filter offset: -0.00043 -0.00029 -0.00058 -0.00137
         0.000000 0.000000 0.000000 0.000000
delay 0.03305, dispersion 0.00021
offset -0.000437

 

-상태확인

root@NanoPC-T3:/home/pi# /etc/init.d/ntp status
● ntp.service - LSB: Start NTP daemon
   Loaded: loaded (/etc/init.d/ntp; bad; vendor preset: enabled)
   Active: active (running) since Wed 2022-10-12 11:22:48 UTC; 1min 36s ago
     Docs: man:systemd-sysv-generator(8)
  Process: 2828 ExecStop=/etc/init.d/ntp stop (code=exited, status=0/SUCCESS)
  Process: 2877 ExecStart=/etc/init.d/ntp start (code=exited, status=0/SUCCESS)
   CGroup: /system.slice/ntp.service
           └─2888 /usr/sbin/ntpd -p /var/run/ntpd.pid -g -u 108:112

Oct 12 11:22:52 NanoPC-T3 ntpd[2888]: Soliciting pool server "주소정보"
Oct 12 11:22:52 NanoPC-T3 ntpd[2888]: Soliciting pool server "주소정보"
Oct 12 11:22:53 NanoPC-T3 ntpd[2888]: Soliciting pool server "주소정보"
Oct 12 11:22:53 NanoPC-T3 ntpd[2888]: Soliciting pool server "주소정보"
Oct 12 11:22:53 NanoPC-T3 ntpd[2888]: Soliciting pool server "주소정보"
Oct 12 11:22:54 NanoPC-T3 ntpd[2888]: Soliciting pool server "주소정보"
Oct 12 11:22:55 NanoPC-T3 ntpd[2888]: Soliciting pool server "주소정보"
Oct 12 11:22:56 NanoPC-T3 ntpd[2888]: Soliciting pool server "주소정보"
Oct 12 11:22:57 NanoPC-T3 ntpd[2888]: Soliciting pool server "주소정보"
Oct 12 11:22:58 NanoPC-T3 ntpd[2888]: Soliciting pool server "주소정보"