"rotor...@yahoo.com" <rotord...@gmail.com> writes: >On Oct 6, 11:52=A0am, Terje Mathisen <terje.mathi...@tmsw.no> wrote:
>> Having an external server fail but still reply (a "falseticker") is an >> expected issue, it is solved by having at least 4 servers. >Right. But even if we require 4, there is the unlikely but possible >scenario of 3 going offline during the same period that the last one >is ill-behaved. In case of a nuclear attack on the US, I think you will have other problems than worrying about the timing on your cluster. There is also a chance that a meteorite will strike your cluster, and then what would you do? Instead of 4, use 12. or 437. Or 9628. >> (BTW, a single clock which jumps 5 minutes will be voted out in any >> redundant setup. It is only if you have just one or two servers, and one >> of these start drifting off slowly (at less than the 500ppm rate) that >> your internal machines would be willing to follow it without logging a >> time jump.) >> >> In your case I would setup at least one internal GPS-based server, and >> then fill out the config with several external servers. This way all >> your internal servers will still agree even if one of your reference >> sourced turn into a falseticker. >It's been suggested earlier in the thread, and would really simplify >the problem, but adding hardware is not at all possible. A far greater possibility is that your internal servers go mad, and deliver the wrong time to the rest of your system. >thanks, >tim _______________________________________________ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
