4.Configure DHCP snooping functions on GigabitEthernet 1/0/3:
a.Click the 
icon of GigabitEthernet 1/0/3 on the interface list.
b.Select the Untrust option for Interface State as shown in Figure 292.
c.Select the Enable option next to Option 82 Support.
d.Select Replace for Option 82 Strategy.
e.Click Apply.
Figure 292 Configuring DHCP snooping functions on GigabitEthernet 1/0/3
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