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Re: Broadcast traffic on vlans leaks into the parent interface on NetBSD-5.1

On Apr 27,  3:15am, David Laight wrote:
} On Tue, Dec 04, 2012 at 10:17:23PM -0800, John Nemeth wrote:
} > 
} >      We use ISC's DHCP server.  As third party software, it is designed
} > to be portable to many systems.  BPF is a fairly portable interface,
} > thus a reasonable interface for it to use.
} One thing I discovered long ago, in an operating system far ... well
} not NetBSD is that dhcp's use of the bpf (equivalent) caused a data
} copy for every received ethernet frame - at considerable cost.
} I've NFI whether this happens withthe current code.

     Given that DHCP is very low traffic, I'm not sure that this really

} Although DHCP has to do strange things in order to acquire the
} original lease, renewing it should really only requires packets
} with the current IP address.

     True.  Renewing a lease takes two packets, a RENEW request, and an
ACK.  Those packets are sent using assigned addresses for both the
destination and the source.

}-- End of excerpt from David Laight

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