rancid moth wrote: > hello, > > not being very familiar with the ntp protocol, and currently introducing > myself to it properly (i.e. have always used though never dug deeply into > it), i have established two ntp services on two different Linux machines. > Both ntp servers are pointing to the _same_ upstream server. There is a > four minute difference in time on the machines. Lets call them machine A > and B. initially i established them to the same time, by synching B's time > from A which itself was synched from the upstream internet ntp server. If i > then modify B's config to also synch from the same upstream source, B, given > enough time, will drift 4 minutes ahead of A. Can someone please point me > to an introductory explanation as to why/how this can occur. > > cheers > moth > >
Basically your setup isn't working for some reason - if you do "ntpq -p" on both boxes you'll probably see that one or both of them are not actually talking to the upstream. As a general rule you need at least four upstream servers for stability (see www.pool.ntp.org for how to get more servers). It's probably a good idea to peer the two local servers and then point them at diverse (overlapping is ok) groups of upstream servers as this will give to a very robust setup. If I had to guess I'd say that a firewall somplace is blocking the ntp packets. John _______________________________________________ questions mailing list [email protected] https://lists.ntp.isc.org/mailman/listinfo/questions
