On Aug 2, 2015, at 2:31 AM, Mike Cook <michael.c...@sfr.fr> wrote: > Can anyone confirm that this is an issue? > > I habitually put an burst directive in my ntp.conf server statements. ex: > > server 129.6.15.30 noselect iburst minpoll 4 maxpoll 6 > server 128.138.140.44 noselect iburst minpoll 4 maxpoll 6 > server 98.175.203.200 noselect iburst minpoll 4 maxpoll 6 > > But in the case of these NIST servers, sometimes they never get out of INIT > state.
iburst isn't usually a problem, but minpoll 4 / maxpoll 6 would be considered abusive without prior arrangements. minpoll 6 is the fastest rate you should query other NTP servers without explicit permission. To be more specific, folks who implement per-client firewall rate rules tend to block clients who exceed ~100 packets per hour. The main point of iburst is to quickly get a downed NTP server back up and serving valid time. That matters most for isolated stratum-2+ servers; if you've already got S1 timesources available and multiple redundant NTP servers locally, using iburst is superfluous. Sure, use iburst on one remote server entry if you want and/or against all of the other NTP peers on your local subnet, but it's not obviously helpful to use iburst everywhere. Regards, -- -Chuck _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
