[ntp:questions] NTP over redundant peer links, undetected loops

Danny Mayer mayer at ntp.org
Sun Feb 15 16:13:01 UTC 2009

Dave Hart wrote:
> On Feb 13, 2:50 am, ma... at ntp.org (Danny Mayer) wrote:
>> I've had only my list of things to do to use only one refid per system
>> rather than based on the IP based being used.
> This certainly seems like a winning idea in terms of loop detection.
> If you do something like this, it would be nice if without extra
> configuration RFC1918 addresses would tend to not be used as refids
> (like unless the only unicast IPv4 address available is RFC1918.

I fail to see what RFC1918 addresses have to do with it. There's always
likely to be a mixture of public/private addresses in an ntp
configuration and I see no point in preferring one over the other. In
addition this ignores the IPv6 addresses and it is intended to tackle
that issue as well. It would be better if these were just a generated
32-bit random number created at startup which is kept for the lifetime
of the server.


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