以下是配置和检查命令
vi /etc/ntp.conf
driftfile /var/lib/ntp/drift
restrict default nomodify notrap nopeer noquery

restrict 127.0.0.1
restrict default notrap nomodify nopeer noquery

server 10.8.8.66 prefer
server 127.127.1.0
Fudge 127.127.1.0 stratum 10

includefile /etc/ntp/crypto/pw
keys /etc/ntp/keys

[root@oradb11 ~]# ntpq -p
remote refid st t when poll reach delay offset jitter

10.8.8.66 .INIT. 16 u - 1024 0 0.000 0.000 0.000
[root@oradb11 ~]# timedatectl
Local time: Fri 2021-05-21 12:04:35 CST
Universal time: Fri 2021-05-21 04:04:35 UTC
RTC time: Fri 2021-05-21 05:10:09
Time zone: Asia/Shanghai (CST, +0800)
NTP enabled: yes
NTP synchronized: no
RTC in local TZ: no
DST active: n/a

[root@oradb11 ~]# ntpstat
synchronised to local net at stratum 6
time correct to within 7948 ms
polling server every 64 s

[root@oradb11 ~]# ntpdate -d 10.8.8.66
21 May 12:05:10 ntpdate[10899]: ntpdate 4.2.6p5@1.2349-o Tue Feb 6 03:08:09 UTC 2018 (1)
Looking for host 10.8.8.66 and service ntp
host found : 10.8.8.66
transmit(10.8.8.66)
receive(10.8.8.66)
transmit(10.8.8.66)
receive(10.8.8.66)
transmit(10.8.8.66)
receive(10.8.8.66)
transmit(10.8.8.66)
receive(10.8.8.66)
server 10.8.8.66, port 123
stratum 9, precision -20, leap 00, trust 000
refid [10.8.8.66], delay 0.02612, dispersion 0.00108
transmitted 4, in filter 4
reference time: e451bdbe.c5d5485d Fri, May 21 2021 13:03:58.772
originate timestamp: e451bdf0.2911311c Fri, May 21 2021 13:04:48.160
transmit timestamp: e451affc.4255705f Fri, May 21 2021 12:05:16.259
filter delay: 0.02628 0.02612 0.02615 0.02621
0.00000 0.00000 0.00000 0.00000
filter offset: 3571.897 3571.898 3571.899 3571.900
0.000000 0.000000 0.000000 0.000000
delay 0.02612, dispersion 0.00108
offset 3571.898966

21 May 12:05:16 ntpdate[10899]: step time server 10.8.8.66 offset 3571.898966 sec