On 01/23/2014 11:00 AM, ardi wrote: > On Thursday, January 23, 2014 9:36:35 AM UTC+1, Marco Marongiu wrote:> Well, > I have come across almost all of the pages, you are mentioning below, > but it seems, i have "combined" the info wrongly for my example...:-)
:-) > Does it mean these minpoll, maxpoll parameters are not needed in most > of the cases? Yes, that's what I mean. > According to book Expert Network Time Protocol from PETER RYBACZYK: I don't have that book. I'd appreciate that anyone in this list that has reviewed the book can give their opinion about it. > "The minpoll and maxpoll parameters represent minimum and maximum > polling intervals for reference clock messages in seconds to the > power of 2. For example, if minpoll=3 and maxpoll=4, the minimum > polling interval would be 8 seconds, and the maximum polling interval > would be 16 seconds." > > What does "minimum and maximum polling intervals for reference clock > messages" mean? > polling = messaging with NTP servers to estimate the offset ??? Yes, but you don't need to query the servers every 16 seconds. Normally, once a peer is selected, ntpd gradually extends the polling interval from 64 to 128 seconds, to 256, 512, and finally 1024. Querying every 16 seconds is a bit obsessive and doesn't bring much more accuracy than the standard settings. Not to mention that your references may rate limit you, or refuse to talk to you altogether. >> First: don't use two servers, it's the worst possible configuration. > > Why not? what if one of the servers fail? then the client can get time from > the other ntp-server. Please, read this section and my previous message carefully: http://www.ntp.org/ntpfaq/NTP-s-algo-real.htm#Q-NTP-ALGO I am not saying that you should use only one server: I am saying that using two is bad, and that you should use four. Ciao -- bronto _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
