Re: Is there any data on packet duplication?

[Sabri Berisha <sabri () cluecentral net>]

----- On Jun 22, 2020, at 11:21 PM, Saku Ytti saku () ytti fi wrote:

Hi Saku,

> On Tue, 23 Jun 2020 at 09:15, Sabri Berisha <sabri () cluecentral net> wrote:
>
> > Yeah, except that unless you use static ARP entries, I can't come up
> > with a plausible scenario in which this would happen for NTP. Assuming
> > we're talking about a non-local NTP server, S3 will not send an NTP
> > packet without first sending an ARP. Yes, your ARP will be flooded,
> > but your NTP packet won't be transmitted until there is an ARP reply.
> > By that time MACs have been learned, and the NTP packet will not be
> > considered BUM traffic, right?
>
> The plausible scenario is the one I explained. The crucial detail is
> MAC timeout (catalyst 300s) being shorter than ARP timeout (cisco 4h).
> So the device generating the packet knows the MAC address, the L2 does
> not.

Aaah yes, fair point! Thanks $deity for default timers that make no sense.

Thanks,

Sabri