question about DHCPACK log entries
David W. Hankins
David_Hankins at isc.org
Thu Mar 1 22:30:03 UTC 2007
On Thu, Mar 01, 2007 at 04:00:18PM -0600, Tim Peiffer wrote:
> /* RFC2131 states the server SHOULD unciast to ciaddr.
> * There are two wrinkles - relays, and when ciaddr is zero.
> * There's actually no mention of relays at all in rfc2131 in
> * regard to DHCPINFORM, except to say we might get packets from
> * clients via them. Note: relays unicast to clients to the
> * "yiaddr" address, which servers are forbidden to set when
> * answering an inform.
> * The solution: If ciaddr is zero, and giaddr is set, go via the
> * relay with the broadcast flag set to help the relay (with no
> * yiaddr and very likely no chaddr, it will have no idea where to
> * send the packet).
> * If the ciaddr is zero and giaddr is not set, go via the source
> * IP address (but you are permitted to barf on their shoes).
> * If ciaddr is not zero, send the packet there always.
It should be noted that this comment is from the DHCPINFORM processing
function, not from the DHCPREQUEST processing function. DHCPACK is
used in two places this way.
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David W. Hankins "If you don't do it right the first time,
Software Engineer you'll just have to do it again."
Internet Systems Consortium, Inc. -- Jack T. Hankins
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