DHCP Relay Limitations

In Layer 2 mode, the switch inserts its own DHCP option 82 with ingress VLAN and ingress port information in the DHCP message it receives from the DHCP clients. Because of this, the DHCP servers must support DHCP option 82. The switch discards DHCP messages with option 82 that it receives from the DHCP clients.

In Layer 3 mode, the feature can only be enabled on the IPv4 interfaces.