DHCP Relay + PPP (your mail)

[Simon Hobson]

David W. Hankins wrote:

>  > Pre-empting the answer I expect ... it's never seemed quite right to
>>  me for the relay to have to listen in the same way on both
>>  interfaces. On the interface(s) that are client facing, then yes, I
>>  see the need for special handling to get the broadcast packets. But
>>  surely it should be able to just open a normal socket on the server
>>  facing interface(s) to handle the unicast packets.
>
>Yeah, we need listen-only behaviour.
>
>Really you want this behaviour reversed for relays - listen only on
>the fallback standard BSD socket, and use the BPF etc sockets for
>transmit-only.
>
>Some day that ship will come in.

So the answer to the original question from Joby Thampan is ... that 
the relay agent will NOT work when the upstream link is PPP. Probably 
because that particular combination wasn't envisaged when it was 
first designed.

Simon