On Aug 10, 2010, at 4:30, Miroslav Lichvar wrote: > I'm considering adding iburst to the pool.ntp.org servers specified in > default ntp.conf in Fedora and RHEL distributions. > > Would that be acceptable?
Hi Miroslav, First of all thanks for asking. I think it'd be acceptable -- if it will actually give you better results I don't know. > On the vendors page there is a note that there should be at most 4-5 > queries per hour. That's for long-running things or custom sntp implementations. The logic is that if you're using sntp in the first place then you don't care enough about what time it is to query very often. ntpd and opentpd are generally fine (because we know they are well behaved). > But ntpd with default minpoll and maxpoll intervals > makes about 43-57 queries in the first hour, so I'd expect adding > iburst will have only a minimal effect on an average server load. The exception would be if you have a whole cluster of servers booting at the same time, using the same DNS servers and maybe even NAT but still using the pool servers. To a limited number of servers it'll look like an onslaught of requests coming from one IP within a short timeframe. > Also, the example on the usage page has four servers specified and > later the document says to not use more than three servers. Where does it say 3? The pool used to only have 3 hostnames but four is better for all the usual reasons if you're running ntpd. - ask -- Ask Bjørn Hansen, http://askask.com/ _______________________________________________ pool mailing list [email protected] http://lists.ntp.org/listinfo/pool
