Re: xntpd not functioning anymore...
On Mon, 13 Dec 1999, Dan Hugo wrote:
> $ntptrace tock.cs.unlv.edu
> tock.CS.UNLV.EDU: stratum 2, offset 0.853196, synch distance 0.04726
> usno.pa-x.dec.com: stratum 1, offset 0.842812, synch distance 0.02371,
> refid 'USNO'
Those offset lines are worrisome. NTP does not deal well with large offsets
and delay (round-trip time) by design (it would be pointless, you can't sync
over such a link), and will promptly exit if it gets worse than 1s. You're
at 0.8s already, and that's way too high.
One thing you -must- do when you have such a bad sync is to run ntpdate in
the same server-set you will run ntp against right before you start ntp.
Debia potato gets this right, don't know about slink.
I'd guess you need a better set of servers as well. A higher stratum (3 or
even 4) closer to you will work much better than a stratum 1 server that is
too distant, you know.
> $ntpdate tock.cs.unlv.edu
> 13 Dec 00:55:08 ntpdate[16494]: no server suitable for synchronization
> found
Network path to tock down? Ntp uses UDP, and doesn't like lossy network
paths. Find a server closer to you, and use more than one. Anything above
200ms for round-trip time is not good, and above 400ms it just won't work
right in my experience.
> I am not sure where to look now. I believe that ipchains is configured
> to allow ntp to communicate, but I could be wrong. I am suspicious of
> my ipchains config.
Don't kill tcp or udp packets from/to the ntp service port, nor delay them.
When in doubt, try ntpq -p <host> to "ping" the servers.
Also, just to be sure... you did notice debian potato packages ntp V4 (don't
know about slink), and used the proper "version 3" strings after the servers
in /etc/ntp.conf for any debian potato machines, didn't you?
--
"One disk to rule them all, One disk to find them. One disk to bring
them all and in the darkness grind them. In the Land of Redmond
where the shadows lie." -- The Silicon Valley Tarot
Henrique Holschuh
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