"Joachim Schrod" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED]
> [...] How many timeservers does one need in an environment as I have > described it? [...] there is *no* demand for high precision, ... I'd say one, then. If timekeeping is not overtly critical, you can do fine with a single server. Occasional loss of Internet connectivity is handled by the primary itself, the backup in my scheme protects (only) from client divergence after total failure of the primary. Not all that interesting, really, except as a way to freak people out who know only that having two servers is bad. Having four servers offers improved fault tolerance mostly against faults in the external references, of which you need a significant number to actually achieve that tolerance. Setting up your own refclocks is great if toys are your thing. You can undoubtedly sell them to management, but personally I like tall trees. I'm very comfortable at stratum 4. [...] > The connection between these two cases is still unclear to me. If I > have own primary servers with refclocks (case 1); should I still set > up internal timeservers (case 2)? Yes. If you care enough to have your own refclocks, you should have a fully-peered layer below them for the clients to see, with ISP and pool fallback associations. In my opinion (but other people are bound to have their own), refclocks don't take the place of the primary server layer. They augment your external references. If nothing else, this way of thinking lets you swap out in-house refclocks without affecting all the leaf nodes, since they only see the interface server layer. Another scenario for refclocks is if you need very good time in a few hosts. You can then distribute a (single) PPS signal to them. You keep mentioning the number of hosts in your questions. That's really not that relevant. Much more interesting are the fault tolerance and accuracy you require, and how you want certain failure modes dealt with. Failure modes I'm aware of include loss of Internet connectivity, Internet connection overload, failure of a single master, internal refclock insanity (1-N), and external reference insanity (1-N). Groetjes, Maarten Wiltink _______________________________________________ questions mailing list [email protected] https://lists.ntp.isc.org/mailman/listinfo/questions
