CentOS 7.x에서 NTP 서버 설정

CentOS 7.x에서 NTP 서버 설정

  • CentOS 7.x에서 네트워크 시간 동기화를 위한 NTP서버를 설치해보자.

yum으로 ntp 를 설치한다.

[root@localhost ~]# yum -y install ntp
Loaded plugins: fastestmirror

...

Dependency Installed:
  autogen-libopts.x86_64 0:5.18-5.el7  ntpdate.x86_64 0:4.2.6p5-19.el7.centos.1

Complete!

ntp 서버 환경을 설정

  • 환경 파일 위치

/etc/ntp.conf

  • 편집기로 화일을 수정하자.

[root@localhost ~]# vi /etc/ntp.conf

# For more information about this file, see the man pages
# ntp.conf(5), ntp_acc(5), ntp_auth(5), ntp_clock(5), ntp_misc(5), ntp_mon(5).

driftfile /var/lib/ntp/drift

# Permit time synchronization with our time source, but do not
# permit the source to query or modify the service on this system.
restrict default nomodify notrap nopeer noquery

# Permit all access over the loopback interface.  This could
# be tightened as well, but to do so would effect some of
# the administrative functions.
restrict 127.0.0.1
restrict ::1

# Hosts on local network are less restricted.
# 18번째줄의 시각 동기를 허용하는 범위를 설정하자. 
restrict 192.168.0.0 mask 255.255.255.0 nomodify notrap

# Use public servers from the pool.ntp.org project.
# Please consider joining the pool (http://www.pool.ntp.org/join.html).
# 동기화 시킬 서버 주소를 한국것으로 바꾸자. 
#server 0.centos.pool.ntp.org iburst
#server 1.centos.pool.ntp.org iburst
#server 2.centos.pool.ntp.org iburst
#server 3.centos.pool.ntp.org iburst
server 1.kr.pool.ntp.org

실행 및 서비스 등록

  • 서비스 실행

[root@localhost ~]# systemctl start ntpd

  • 서비스 등록

[root@localhost ~]# systemctl enable ntpd

동작확인

  • 올바르게 동작하는지 학인해 보자.

[root@localhost ~]# ntpq -p

remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
*dadns.cdnetwork 133.100.8.2      2 u   24   64    1    2.903   -0.610   0.000