DHCP server ignores directed DHCPREQUEST on renewal

[David W. Hankins]

On Sat, May 06, 2006 at 08:08:59AM -0700, Vladislav Belogrudov wrote:
> I try to test dchpd with provided dhclient.
> The procedure (discover,lease renewal) works fine
> but with some minor drawbacks. When the client wants
> to renew lease it sends unicast message to dchpd
> several times and dhcpd ignores it. Then client
> starts broadcasting request and gets acknowledgement.
> I wonder why server ignores first renewal requests..

Is it possible that the client's request is being delivered via an
interface other than eth0 on the dhcp server?

> I found that such directed DHCPREQUEST messages are
> ignored by the server in fallback_discard()

The fallback interface discards everything it receives - it is only
used to transmit unicast messages (broadcasts go via the LPF sockets,
and we could do unicasts there too, but we'd have to build our own
routing table, arp, etc...).

-- 
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