Michael wrote: .. > 3) Problem 1 > If I tell these servers to sync directly to the GPS server as clients, they > do suceed, but then > they lose sync for a few minutes and then find it again etc etc. NTP reports > in /var/log/messages > that "No servers reachable", but I have sat there with tcpdump running > watching the UDP > request/responses ticking away with no problems whatsoever. No packets are > lost at all. > But NTP just doesnt seem to like whats going on. > However, if I make the client "burst" to the server, it never seems to lose > sync at all. Why I need > to use burst on a LAN when I cant see any packet loss, I dont know but it > seems to fix the problem. > > 4) Problem 2 > Now, if I sync a server lets call it A, off the GPS server, then try to sync > the other servers off A, none > of them will sync at all even though NTP can see server A and ntpq reports a > reach of 377, the offset is > < 1ms and the jitter is < .01ms and tcpdump sees all the UDP > request/response packets without any problems. > So communication with the server appears to be fine, but NTP just doesnt > want to sync up at all. > > Anybody got any ideas as to what is happening as I am going slowly mad.
Going mad will not help at all :). It might be iptables trying to handle the UDP packets in a "statefull" way. The longer ntpd is running the larger the polling intervall becomes and iptables decides that it is "not related" traffic and it might get dropped. Just my 2 cents. Eddy _______________________________________________ questions mailing list [email protected] https://lists.ntp.isc.org/mailman/listinfo/questions
