ntpd diagnostics

ntpq -pn

ntpq> as

ind assID status conf reach auth condition last_event cnt
===========================================================
 1 29157 9614 yes yes none sys.peer reachable 1
 2 29158 9014 yes yes none reject reachable 1

ntpq> rv 29158
assID=29158 status=9014 reach, conf, 1 event, event_reach,
srcadr=time, srcport=123, dstadr=192.168.16.72, dstport=123, leap=00,
stratum=3, precision=-6, rootdelay=62.500, rootdispersion=10733.246,
refid=172.18.0.104, reach=377, unreach=0, hmode=3, pmode=4, hpoll=7,
ppoll=6, flash=400 peer_dist, keyid=0, ttl=0, offset=-76.051,
delay=5.202, dispersion=18.634, jitter=59.528,
reftime=dda1b0a9.ca84f3f0 Mon, Oct 30 2017 15:07:37.791,
org=dda1b37f.c253cd06 Mon, Oct 30 2017 15:19:43.759,
rec=dda1b37f.f06440f2 Mon, Oct 30 2017 15:19:43.939,
xmt=dda1b37f.d5a61c0a Mon, Oct 30 2017 15:19:43.834,
filtdelay= 104.46 243.56 5.58 5.20 125.15 6.32 5.97 111.05,
filtoffset= -127.71 -203.04 -69.73 -76.05 -132.87 -63.20 -76.46 -126.81,
filtdisp= 15.63 16.57 17.55 18.49 19.48 20.43 21.37 22.32

Here look for the flash id peer_dist are too many hops for ntp to work.