[nsp] dhcp and redundancy via hsrp

[Jochen Kaiser]

hi,

while sniffing our dhcpd, I do see the following strange behaviour:

[...]
Router2 -> $DHCP-SERVER DHCP/BOOTP DHCPDISCOVER
Router1 -> $DHCP-SERVER DHCP/BOOTP DHCPDISCOVER
$DHCP-SERVER -> Router2 DHCP/BOOTP DHCPOFFER
$DHCP-SERVER -> Router1 DHCP/BOOTP DHCPOFFER
Router1 -> $DHCP-SERVER DHCP/BOOTP DHCPREQUEST
Router2 -> $DHCP-SERVER DHCP/BOOTP DHCPREQUEST
[...]

The effect comes because of our reduncy concept. Both routers
are in the same L2 network (organized via HSRP) and both have 
the udp-helper enabled. So both routers forward the dhcp-request
to their helper address and the dhcp-server answers to both of
them... that's surely not what one wants.

Is there a way to avoid this? 
(in the router config or at the dhcp-server?)

regards,
Jochen

-- 
Dipl. Inf. Jochen Kaiser, GPG 0x3C93A870, phone +49 9131 85-28681
Network Administration  mailto:jochen.kaiser at rrze.uni-erlangen.de
Regionales Rechenzentrum Universitaet Erlangen-Nuernberg, Germany
Homepage and PublicKey: http://ipv6.rrze.uni-erlangen.de/~unrz111