I am having an issue trying to configure ip dhcp snooping. I have a windows dhcp server on my server room switch (6500). All of my vlan interfaces are on my core (6500) with helper ip addresses. I have enabled snooping, trusted the port the dhcp server is on and enabled trusted on the upstream and downstream etherchannel links. Basically my access switches forward all traffic to the core interface, then the interface passes it to the server room access switch. Works fine without snooping. No go with snooping. I am receiving dropped packets because of "Nonzero giaddr". Obviously my packets are being dropped but I do not understand why. This doesn't seem to be a hard protocol but I just can't seem to get it. Any ideas?