简介
chrony是网络时间协议(NTP)的通用实现,chrony中包含两个程序，chronyd是一个可以在启动时启动的守护程序，chronyc是一个命令行界面程序。
配置文件：chrony.conf
server：时间服务器地址；
allow ：允许客户端；
deny ：拒绝客户端；；
local stratum 10：即使自己未能同步网络时间，也允许授时给其它客户端；
环境
CentOS Linux release 7.6
server： 10.120.123.8
client ： 10.120.123.9
安装Chrony
yum install -y chrony
server端(10.120.123.8)
vim/etc/chrony.conf
allow 10.120.123.0/24
启动服务
systemctl start chronyd.service
systemctl enable chronyd.service
查看端口
netstat -nlup | grep chronyd
udp 0 0 0.0.0.0:123 0.0.0.0:* 9091/chronyd
udp 0 0 127.0.0.1:323 0.0.0.0:* 9091/chronyd
udp6 0 0 ::1:323 :::* 9091/chronyd
client端(10.120.123.9)
vim/etc/chrony.conf
server 10.120.123.8 iburst
#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
启动服务
systemctl start chronyd.service
systemctl enable chronyd.service
查看同步状态
1,chronyc sourcestats
210 Number of sources = 1
Name/IP Address NP NR Span Frequency Freq Skew Offset Std Dev
==============================================================================
10.120.123.8 0 0 0 +0.000 2000.000 +0ns 4000ms
2.chronyc sources -v
210 Number of sources = 1
.-- Source mode ‘^‘ = server,‘=‘ = peer,‘#‘ = local clock.
/ .- Source state ‘*‘ = current synced,‘+‘ = combined,‘-‘ = not combined,| / ‘?‘ = unreachable,‘x‘ = time may be in error,‘~‘ = time too variable.
|| .- xxxx [ yyyy ] +/- zzzz
|| Reachability register (octal) -. | xxxx = adjusted offset,|| Log2(Polling interval) --. | | yyyy = measured offset,|| \ | | zzzz = estimated error.
|| | | MS Name/IP address Stratum Poll Reach LastRx Last sample
===============================================================================