On 2011-03-22, David J Taylor <david-tay...@blueyonder.co.uk.invalid> wrote: >> He can do that if he wants to. That was why the -q option was designed >> into ntpd-- one time setting of the clock time. However it cannot create >> a drift file. If he wants a drift file then as you say, he must run it >> continuously. > > You could look at it that way, Bill, if all he needs is a one-off setting. > However, Prashant says he wants to run it periodically, which doesn't > really make sense. Rather than a periodic run, he should leave ntpd > running continuously, which is what ntpd is designed for.
ntpd -q is a replacemtn for ntpdate, which was typically run from cron, and he is doing, and it is an "acceptable" procedure if for example you do not want a daemon running which could have (unknown to you) security issues. It is also a bit unclear how to switch off the server role of ntpd and he may not want others querying his machine. On the other had it comes at a cost of far worse clock discipline and the probability of the computer jumping backwards in time. > > Prashant, the fact that the server capability is already built-in to ntpd > in no way detracts from using ntpd just as a client for your PC to keep > the time spot-on. Just leave it running all the time as it uses very > little resources. It will then compute the drift information after (IIRC) > one hours of running, and it will keep your PC clock correct by adjusting > the rate, rather than bang-bang adjustments of the time. One hour? More like 10 hr. ntpd is really bad at recovering from changes, and switchon is a big change. After 1 hr the drift is liable to be way off, as ntpd alters the drift to bring the clock back into line. > > Cheers, > David > _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
