NTP sync problem - "configured, authenticated, insane, invalid, unsynced, stratum 16"

[nedeljkovicd]

Hi everybody,

i'm configuring remote office router, IPSec over MPLS connection, and ntp can't sync with ntp server.

RMToff#sh ntp associations detail
10.32.1.11 configured, authenticated, insane, invalid, unsynced, stratum 16
ref ID 0.0.0.0, time 00000000.00000000 (00:00:00.000 UTC Mon Jan 1 1900)
our mode client, peer mode unspec, our poll intvl 64, peer poll intvl 64
root delay 0.00 msec, root disp 0.00, reach 0, sync dist -2515.213
delay 0.00 msec, offset 0.0000 msec, dispersion 16000.00
precision 2**5, version 3
org time D714956E.8B2A722A (11:20:14.543 UTC Wed May 7 2014)
rcv time D714B158.1C9A76DD (13:19:20.111 UTC Wed May 7 2014)
xmt time D714B158.19A8C69C (13:19:20.100 UTC Wed May 7 2014)
filtdelay =     0.00    0.00    0.00    0.00    0.00    0.00    0.00    0.00
filtoffset =    0.00    0.00    0.00    0.00    0.00    0.00    0.00    0.00
filterror =  16000.0 16000.0 16000.0 16000.0 16000.0 16000.0 16000.0 16000.0

RMToff#sh clock

.13:20:57.351 UTC Wed May 7 2014

I suppose that differecnce between org and rcv time shoudn't be so large, but have no idea what causes it. Any ideas?

Thanks in advance!

[Marvin Rhoads]

I suspect it's because the client sees the server at stratum 16 (not synced with a valid source).

To see more precisely why the client isn't syncing ("insane" server), you can "debug ntp validity" and see which of the sanity checks is failing. 

Here is a good reference article for that and other troubleshooting tips.

You could also try manually setting your local clock and then seeing if it syncs. I have seen some devices not sync if the offset is too great.

[Mark Ruhland]

Yes that is correct, if the host time is more than 1024 seconds off from the received time it will mark the source as insane.