I would like to implement DHCP snooping function beetween a cat4510 (name switch A) with one DHCP server connected to it (vlan_dhcp_server) , and an access-switch (name switch E, DHCP client on vlan_dhcp_client) also connected throught several switches (names switches: B, switch C, switch D) to switch E.
DHCP client and DHCP server are not on the same vlans (there is a router)
On switch A,
the interface to the DHCP server is in a trusted mode
the interface to the router is in a trusted mode
dhcp snooping activated on vlan vlan_dhcp_client even if there is no client directly connected
on switch E,
no DHCP snooping definition
on switches B, C and D
no DHCP definition
on the router (switch cat4500 acting also as a router):
the interface to swith A is in a trust mode, but dhcp snooping isn't running/activated
1) do I have to implement also DHCP snooping to all switches between swith A and switch E (B, C, and D) ?
(with trusted interface to switch A, activation on vlan_dhcp_client
2) on the router
do I have to enable DHCP snooping also on the router globally (even if there is no client from any vlans directly connected to the router (it is a cat4500 box) ?
ip dhcp snooping
still on the switch-router box, do I have to implement DHCP snooping on vlan_dhcp_client even if there is no client on this box directly connected?
ip dhcp snooping vlan <vlan_dhcp_client>