Thank you for your detailed examples Steve. You have been very helpful. I'm preparing to leave work for the Holiday weekend. If you are also a US citizen, I'll wish you an enjoyable Thanksgiving Day.
./Cal On Wed, 2008-11-26 at 18:06 +0000, Steve Kostecke wrote: > On 2008-11-25, Cal Webster <[EMAIL PROTECTED]> wrote: > > > On Tue, 2008-11-25 at 21:10 +0000, Steve Kostecke wrote: [...] > > > >> > Unfortunately, connection to the Internet is not an option I'm > >> > allowed to consider. > >> > >> Another option you could consider is the dumbclock driver. This uses > >> a serial link to transfer time stamps from one system to another. > > > > Thanks but I'm afraid this would be of little use to me since most of > > the systems are separated by brick and mortar, connected to each other > > through DSL links on site. > > This was a suggestion of a means of getting timestamps to the primary > time server in your time island. Distribution of the time to other ntpds > would occur over the network. > > > So, if I wanted to setup my 4 NTP servers to look to the one with the > > best local clock as the master (if you've been following this thread) > > but fall back to Orphan mode when it became unreachable, could you > > give me an example of how the configs might look? I could later point > > them to the one with the GPS time reference as master when I get it > > setup. > > > > My main concern is to continue to have an NTP server available in > > each of 3 buildings even if they loose connectivity with each other > > for some reason. I currently have at least one NTP service running in > > each building, serving clients on MS Windows, Linux, and various Unix > > flavors. > > You need to set up the time servers for the orphan group in a "mesh" > (i.e. they all need to poll each other for the time). You may use any > NTP association mode for this purpose. > > The following examples are incomplete; you need to add the drift file, > any desired restrictions, etc. > > *** Unicast: > > # Master Time Server * > # setting minpoll 4 makes this ntpd available to clients > # approximately 50 seconds after startup > server 127.127.1.0 minpoll 4 > fudge 127.127.1.0 > > # Bldg A Time Server > tos orphan 10 > server master.server.ip.address iburst > server bldg.B.ip.address iburst > server bldg.C.ip.address iburst > > # Bldg B Time Server > tos orphan 10 > server master.server.ip.address iburst > server bldg.A.ip.address iburst > server bldg.C.ip.address iburst > > # Bldg C Time Server > tos orphan 10 > server master.server.ip.address iburst > server bldg.A.ip.address iburst > server bldg.B.ip.address iburst > > If you have additional time servers create similar ntp.conf files and > make sure that each servers knows about the others. > > *** Manycast: > > This mode provides automatic server discovery and creates unicast > associations. To use Manycast your server must be configured for to > support Multicast addresses _or_ you need a site-wide broadcast address > (i.e. every one on the same subnet). You also need to be comfortable > with setting up symmetric keys. > > One advantage to using Manycast mode is that you can drop in additional > time servers without reconfiguring all of your existing time servers. > > # Master Time Server * > # setting minpoll 4 makes this ntpd available to clients > # approximately 50 seconds after startup > server 127.127.1.0 minpoll 4 > fudge 127.127.1.0 > manycastserver broadcast.or.multicast.address > > # Bldg Time Servers > # each "building time server" uses this file > tos orphan 10 > manycastclient broadcast.or.multicast.address key N > manycastserver broadcast.or.multicast.address > > * Note: > > I am suggesting the use of the Undisciplined Local Clock on your Master > Time Server primarily beacuse The Undisciplined Local Clock has some > "knobs" which may be used to interactively trim its performance through > ntpdc. Orphan Mode, on the other hand, does not provide these knobs. > > There is also a rootdispersion issue with Orphan Mode for stable > releases up to 4.2.4p5 and for development releases before 4.2.5p101. I > am currently conducting some tests. > _______________________________________________ questions mailing list [email protected] https://lists.ntp.org/mailman/listinfo/questions
