3Com WX3000 operation manual Dhcp Snooping Configuration Example

To do…	Use the command…	Remarks
	ip check source ip-address	Required
Enable IP filtering		By default, this function is
	[ mac-address ]
		disabled.
Create an IP static binding	ip source static binding	Optional
	ip-address ip-address	By default, no static binding
entry
	[ mac-address mac-address]	entry is created.

zEnable DHCP snooping and specify trusted ports on the device before configuring IP filtering.

zYou are not recommended to configure IP filtering on the ports of an aggregation group.

DHCP Snooping Configuration Example

DHCP-Snooping Option 82 Support Configuration Example

Network requirements

As shown in Figure 3-6, GigabitEthernet 1/0/5 of Switch is connected to the DHCP server, and GigabitEthernet 1/0/1, GigabitEthernet 1/0/2, and GigabitEthernet 1/0/3 are respectively connected to Client A, Client B, and Client C.

zEnable DHCP snooping on Switch.

zSpecify GigabitEthernet 1/0/5 on Switch as a trusted port for DHCP snooping.

zEnable DHCP-snooping Option 82 support on Switch and set the remote ID field in Option 82 to the system name of Switch. Set the circuit ID sub-option to “abcd” in DHCP packets from VLAN 1 on GigabitEthernet 1/0/3.

Figure 3-6Network diagram for DHCP-snooping Option 82 support configuration

	DHCP Server
GE1/0/5	Switch
	DHCP Snooping
GE1/0/1	GE1/0/3
	GE1/0/2

Client A Client B Client C

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