Users Guide

OS10(conf-if-eth1/1/4)# ip address dhcp
OS10(conf-if-eth1/1/4)# end
DHCP snooping switch as relay agent
This example uses a simple topology with a DHCP snooping switch congured as a DHCP relay agent. A DHCP server and a DHCP client
are connected to the snooping switch through dierent VLANs. A rouge DHCP server attempts to pose as a legitimate DHCP server. With
a conguration similar to the following, the DHCP snooping switch drops packets from the rouge DHCP server which is connected to an
untrusted port.
DHCP snooping switch
OS10# configure terminal
OS10(config)# ip dhcp snooping
OS10(config)# end
OS10# configure terminal
OS10(config)# interface vlan 100
OS10(conf-if-vl-100)# no shutdown
OS10(conf-if-vl-100)# ip address 10.1.1.1/24
OS10(conf-if-vl-100)# ip helper-address 10.2.1.2
OS10(conf-if-vl-100)# exit
OS10(config)# interface vlan 200
OS10(conf-if-vl-200)# no shutdown
OS10(conf-if-vl-200)# ip address 10.2.1.1/24
OS10(conf-if-vl-200)# exit
OS10(config)# interface ethernet 1/1/2
OS10(conf-if-eth1/1/2)# no shutdown
OS10(conf-if-eth1/1/2)# switchport access vlan 200
OS10(conf-if-eth1/1/2)# ip dhcp snooping trust
OS10(conf-if-eth1/1/2)# exit
OS10(config)# interface ethernet 1/1/4
OS10(conf-if-eth1/1/4)# no shutdown
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System management