I was working on dhcp relay in Linux and came to know following things:
We cannot run the command giving only one interface , either it has to be all or none.
So it can be like
dhcrelay –d serverip
or
dhcrelay –d –i eth0 -i eth1 serverip
Basically all the interfaces, including the one on which the server is connected,
is to be specified in the command .If we give only one interface it will
silently discard the packet.
Please see below bug for more information.
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=648401