[Peter Silva]

Alan Cox wrote:

>>If you don't have an internet link.  then pick nodes to run fake 
>>reference clocks at a high stratum
>>The machines, using NTPD will still be accurately synched.  The only 
>>"problem" is that
>>the time might not agree with UTC, but if there's no internet link, 
>>who's going to know?
>>
>
>What if half the nodes have an internet link
>
Then the half that doesn't will listen to the half that does (assuming 
you pick your ntp server
nodes wisely enough to have some on each half), and chime together with 
them.
The stratum id's on the sources will indicate to ntpd that that is the 
Right Thing to do.

If the nodes with the internet link are all down, it won't matter 
either, because NTP adjusts
the speed of clocks over the long term to have them tick at the same 
rhythm, so all the
clocks should drift ever so slowly and gracefully away from UTC while 
the Internet
link is gone, then creep back slowly when a disciplined clock returns.   
They will not
run wild the moment they lose contact with a good server.

>
>NTP is certainly fault tolerant itself, but when you start trying to use
>the results of multiple split NTP groups to figure out who is allowed into
>the cluster it gets more entertaining.
>
>NTP within a cluster is definitely a very good idea
>
yes, that's all I meant to convey.

>
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