Richard B. Gilbert wrote:
> Rob wrote:
>> Richard B. Gilbert wrote:
>>> The fundamental problem with two servers is this: which one do you
>>> believe when the two differ? You know that at least one of the two must
>>> be wrong but it's impossible to determine WHICH one!
>>
>> This is not relevant when the two servers return the same time within
>> the margin that one considers acceptable.
>>
>
> It would be wonderful if we could rely on two servers always agreeing!
>
> The last "NTP Survey" (google for it) found at least one server that
> responded with the wrong year!
Read what the original poster was asking about.
>> So when you have two servers that each are synchronized to the same
>> GPS PPS clock, there should be no problem. They return the same time
>> or no response at all (when down) and the clients will lock on either
>> of them without problem.
>>
> And when that "GPS PPS Clock" fails? It should not but that's not the
> same as cannot!
Not relevant.
Read what the original poster was asking about.
He describes a system he designed, and obviously he understands the
limitations of his design.
He does not want to hear about his clock failing. If that would be an
issue he would have designed two clocks into his system.
He wants to know if two NTP servers can redundantly serve time, and
if clock hopping would be an issue.
That is not like asking if the universe could collapse next year. |