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.
--
ISC Training! http://www.isc.org/training/ training at isc.org
Washington DC area, April 16-20 2007. DNS & BIND, DDNS & DHCP.
--
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
More information about the dhcp-users
mailing list