# /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4 ::1 localhost localhost.localdomain localhost6 localhost6.localdomain6 172.16.10.252 ps-a.local 172.16.20.252 ps-b.local 172.16.30.252 ps-c.local 172.16.40.252 ps-d.local 172.16.50.252 ps-e.local
ps-a.local # /etc/ntp.conf
restrict 127.0.0.1 restrict ::1 restrict 172.16.0.0 mask 255.255.0.0 nomodify notrap logfile /var/log/ntpd driftfile /var/lib/ntp/ntp.drift statsdir /var/lib/ntp/ statistics loopstats peerstats clockstats filegen loopstats file loopstats type day enable filegen peerstats file peerstats type day enable filegen clockstats file clockstats type day enable tos orphan 1
ps-b.local # /etc/ntp.conf
server ps-a.local iburst
ps-b # ntpq -p
remote refid st t when poll reach delay offset jitter
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*ps-a.local .LOOP. 1 u 169 512 377 0.358 4.543 1.007