CCNP DHCP Snooping
DHCP Snooping is used to block untheorized DHCP server.
Step 1) Enable DHCP snooping Globally
Switch(config)#ip dhcp snooping
Switch(config)#ip dhcp snooping vlan 30
Step 2) Apply to the interface that need to be trusted (By default all other ports will be untrusted)
Switch(config)#interface gigabitethernet1/0/1
Switch(config-if)#ip dhcp snooping trust
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