On Monday 05 June 2006 15:28, Jacques-André Eberhard wrote: > Bonjour, > > Nous avons un Windows 2000 server SP4, puis un VmWare server et une SLES9 > avec le .rpm de ntp installé.
Bon, j'ai relu un bout du manuel de ntpd. Il y a pas mal d'explication et le mieux serait de lire ce manuel en detail. Je n'en mets qu'un petit bout dasns ce mail. Ma conclusion est : executer ntpdate avant de demarer xntp, puis s'assurer que l'interval mentionne ci-dessous reste a 64 secondes. dc POLL INTERVAL CONTROL This version of NTP includes an intricate state machine to reduce the network load while maintaining a quality of synchronization consistent with the observed jitter and wander. There are a number of ways to tailor the operation in order enhance accuracy by reducing the interval or to reduce network overhead by increasing it. However, the user is advised to carefully consider the consequenses of changing the poll adjustment range from the default minimum of 64 s to the default maximum of 1,024 s. The default minimum can be changed with the tinker minpoll command to a value not less than 16 s. This value is used for all configured associations, unless overriden by the minpoll option on the configuration command. Note that most device drivers will not operate properly if the poll interval is less than 64 s and that the broadcast server and manycast client associations will also use the default, unless overriden. In some cases involving dial up or toll services, it may be useful to increase the minimum interval to a few tens of minutes and maximum interval to a day or so. Under normal operation conditions, once the clock discipline loop has stabilized the interval will be increased in steps from the minumum to the maximum. However, this assumes the intrinsic clock frequency error is small enough for the discipline loop correct it. The capture range of the loop is 500 PPM at an interval of 64s decreasing by a factor of two for each doubling of interval. At a minimum of 1,024 s, for example, the capture range is only 31 PPM. If the intrinsic error is greater than this, the drift file ntp.drift will have to be specially tailored to reduce the residual error below this limit. Once this is done, the drift file is automatically updated once per hour and is available to initialize the frequency on subsequent daemon restarts. _______________________________________________ gull mailing list [email protected] http://lists.alphanet.ch/mailman/listinfo/gull
