[ntp:questions] Re: Different types of associations in the ntpq billboard

Heiko Gerstung heiko.gerstung_removeme_ at meinberg.de
Tue Apr 11 14:03:37 UTC 2006

Danny Mayer wrote:
> Ronan Flood wrote:
>> mayer at ntp.isc.org (Danny Mayer) wrote:
>>>> Looking at ntpq_ops.c/decodeaddrtype(), it only shows "b" for an IPv4
>>>> non-multicast destination address ending in 255 -- I guess you're
>>>> subnetting, or using IPv6.
>>> That's not surprising since that basically defines broadcasting. IPv6
>>> does not have broadcast.
>> Fair enough for IPv6 then, but in IPv4 if your local net is say
>>, your broadcast address is
>> Perhaps some use should be made of pmode=MODE_BROADCAST?
> Probably, but ntpq receives the data as-is and doesn't have access to
> that information. I will have to take another look at the definition of
> broadcast before I respond to the first part of your question.
The information that this is a broadcast packet should be in the ntp 
packet itself, no? (mode 5 = broadcast)

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