以一个阿里云VM上的输出为例
[root@CentOS ~]# ntpq -pn
remote refid st t when poll reach delay offset jitter
==============================================================================
127.127.1.0 .LOCL. 10 l - 64 0 0.000 0.000 0.000
#2001:4860:4806: 71.79.79.71 2 u 1012 1024 357 280.158 -15.630 3.135
#2001:4860:4806: 71.79.79.71 2 u 816 1024 377 262.399 -24.971 2.702
#2001:4860:4806: 71.79.79.71 2 u 708 1024 377 364.687 -13.306 4.368
#2001:4860:4806: 71.79.79.71 2 u 606 1024 377 381.816 -28.115 3.897
*182.92.12.11 10.137.38.86 2 u 327 1024 377 0.245 0.810 0.792
+120.25.115.19 10.137.38.86 2 u 824 1024 377 35.800 -0.694 0.819
-120.25.115.20 10.137.38.86 2 u 411 1024 377 35.496 2.679 0.930
+120.25.108.11 10.137.38.86 2 u 947 1024 377 38.739 2.205 0.807
+115.28.122.198 10.137.38.86 2 u 753 1024 377 11.627 0.952 0.938
-10.143.33.49 10.143.0.44 3 u 818 1024 377 28.970 -1.337 0.805
+10.143.33.50 10.143.0.44 3 u 843 1024 377 32.689 0.179 0.832
+10.143.33.51 10.143.0.44 3 u 838 1024 377 32.612 0.252 0.848
+10.143.0.44 10.137.38.86 2 u 889 1024 377 25.149 0.277 0.786
+10.143.0.45 10.143.0.44 3 u 853 1024 377 32.282 0.468 0.808
#10.143.0.46 10.143.0.44 3 u 983 1024 377 29.398 -1.656 0.943
remote是远程ntp server的地址在remote前面有各种+ – x #等，也是有相应得含义的
x discarded by intersection algorithm
. discarded by table overflow (not used)
- discarded by the cluster algorithm
+ included by the combine algorithm
# backup (more than tos maxclock sources)
* system peer
o PPS peer (when the prefer peer is valid)
refid
association ID or kiss code
st
stratum层级，GPS为0级，GPS授时服务器为一级。最大不能超过15级。
t是peer类型
u: unicast or manycast client
b: broadcast or multicast client
l: local (reference clock)
s: symmetric (peer)
A: manycast server
B: broadcast server
M: multicast server
when
上一次收到包的时间间隔
poll
同步间隔2^n次方
reach
查询到得总次数
delay
往返延迟,单位是ms
offset
远程时间减去本机时间的差值，单位是ms。为正数说明本地时间比远程时间慢，为负数说明本地时间更快。
jitter
衡量远程服务器时间稳定的一个参数，越小说明远程时间偏差越小。
参考资源
- https://www.eecis.udel.edu/~mills/ntp/html/decode.html#peer
- https://www.eecis.udel.edu/~mills/ntp/html/ntpq.html