설치환경 $ cat /etc/redhat-release CentOS Linux release 7.9.2009 (Core) 설치 $ yum -y install ntp Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: mirror.kakao.com * extras: mirror.kakao.com * updates: mirror.navercorp.com Resolving Dependencies --> Running transaction check ---> Package ntp.x86_64 0:4.2.6p5-29.el7.centos.2 will be installed --> Processing Dependency: n..