OS환경 : Oracle Linux 7.5 (64bit)
방법 : Oracle Linux 7에서 NTP 설정
NTP란?
NTP(Network Time Protocol)는 인터넷상의 시간을 정확하게 유지시켜 주기 위한 통신망 시간 규약임
라디오나 원자시계에 맞추어 시간을 조정하며 밀리초 1/1000초 단위까지 시간을 맞출 수 있음
Oracle RAC 설치 시에 정확한 시간 동기화를 위해 설정할 수 있음
NTP 설정
NTP 패키지 설치
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 | # yum install -y ntp Loaded plugins: langpacks, ulninfo Resolving Dependencies --> Running transaction check ---> Package ntp.x86_64 0:4.2.6p5-25.0.1.el7_3.2 will be installed --> Processing Dependency: libopts.so.25()(64bit) for package: ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 --> Running transaction check ---> Package autogen-libopts.x86_64 0:5.18-5.el7 will be installed --> Finished Dependency Resolution Dependencies Resolved ============================================================================================================================================================= Package Arch Version Repository Size ============================================================================================================================================================= Installing: ntp x86_64 4.2.6p5-25.0.1.el7_3.2 ol7 547 k Installing for dependencies: autogen-libopts x86_64 5.18-5.el7 ol7 65 k Transaction Summary ============================================================================================================================================================= Install 1 Package (+1 Dependent package) Total download size: 611 k Installed size: 1.5 M Downloading packages: ------------------------------------------------------------------------------------------------------------------------------------------------------------- Total 90 MB/s | 611 kB 00:00:00 Running transaction check Running transaction test Transaction test succeeded Running transaction Installing : autogen-libopts-5.18-5.el7.x86_64 [ ] 1/2 Installing : autogen-libopts-5.18-5.el7.x86_64 [############################################# ] 1/2 Installing : autogen-libopts-5.18-5.el7.x86_64 [########################################################################################## ] 1/2 Installing : autogen-libopts-5.18-5.el7.x86_64 [############################################################################################# ] 1/2 Installing : autogen-libopts-5.18-5.el7.x86_64 [################################################################################################## ] 1/2 Installing : autogen-libopts-5.18-5.el7.x86_64 [################################################################################################### ] 1/2 Installing : autogen-libopts-5.18-5.el7.x86_64 1/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [ ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [# ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [##### ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [######## ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [############ ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [################# ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [###################### ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [########################## ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [############################### ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [################################### ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [######################################## ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [############################################ ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [################################################# ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [##################################################### ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [########################################################## ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [############################################################### ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [################################################################### ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [###################################################################### ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [########################################################################### ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [############################################################################### ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [################################################################################## ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [####################################################################################### ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [######################################################################################## ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [######################################################################################### ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [############################################################################################# ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [############################################################################################## ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [############################################################################################### ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [################################################################################################ ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [################################################################################################# ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [################################################################################################## ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 [################################################################################################### ] 2/2 Installing : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 2/2 Verifying : ntp-4.2.6p5-25.0.1.el7_3.2.x86_64 1/2 Verifying : autogen-libopts-5.18-5.el7.x86_64 2/2 Installed: ntp.x86_64 0:4.2.6p5-25.0.1.el7_3.2 Dependency Installed: autogen-libopts.x86_64 0:5.18-5.el7 Complete! |
NTP 설정파일 수정
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 | 기존 # vi /etc/ntp.conf "/etc/ntp.conf" 58L, 1992C# For more information about this file, see the man pages . . server 0.rhel.pool.ntp.org iburst server 1.rhel.pool.ntp.org iburst server 2.rhel.pool.ntp.org iburst server 3.rhel.pool.ntp.org iburst . . 변경 # vi /etc/ntp.conf "/etc/ntp.conf" 58L, 1992C# For more information about this file, see the man pages . . #server 0.rhel.pool.ntp.org iburst #server 1.rhel.pool.ntp.org iburst #server 2.rhel.pool.ntp.org iburst #server 3.rhel.pool.ntp.org iburst server 1.kr.pool.ntp.org server 0.asia.pool.ntp.org server 2.asia.pool.ntp.org . . . |
기존 server 구문 주석 후 server 구문 3줄 추가
서버 기동시 실행되게끔 NTP 서비스 등록
1 2 | # systemctl enable ntpd.service Created symlink from /etc/systemd/system/multi-user.target.wants/ntpd.service to /usr/lib/systemd/system/ntpd.service. |
*참고
Linux 6 이하 버전에서 서비스 등록 명령 및 시작 명령
1 2 | # chkconfig ntpd on # /etc/init.d/ntpd start |
NTP 서비스 기동
1 | # systemctl start ntpd.service |
NTP 상태 확인
1 2 3 4 5 6 | # ntpq -p remote refid st t when poll reach delay offset jitter ============================================================================== send.mx.cdnetwo 216.239.35.8 2 u 21 64 1 8.237 0.106 0.000 cdns-lhr-02.ptc 195.43.74.123 2 u 20 64 1 177.489 19.140 0.000 203.107.6.88 10.137.55.181 2 u 19 64 1 53.948 4.282 0.000 |
* : 현재 sync 를 받고 있음을 의미
+ : ntp 알고리즘에 의해 접속은 가능하지만 sync 를 하고 있지는 않음을 의미
- : ntp 알고리즘에 의해 접속은 가능하지만 sync 가능 리스트에서 제외
blank : 접속이 불가능함을 의미
remote는 sync 를 하는 straum 2 서버주소를 가리키며,
refid는 각 straum 2 서버가 현재 sync 를 하고 있는 straum 1 서버를 보여줌
st가 16일 경우 해당 서버에 접속 할 수 없음을 의미함
(타 블로그는 remote의 주소 앞에 *이나 +이 붙는데 현재 나는 아무것도 나오지않음)
참조 : https://webdir.tistory.com/120
http://blog.naver.com/wizardkyn/220840483581
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