3Com 2928 User Guide - Page 327

DHCP Snooping Configuration Example, Network requirements, Configuration procedure, Table 3-3

Page 327 highlights

Table 3-3 DHCP snooping user information configuration items Item Description IP Address MAC Address This field displays the IP address assigned by the DHCP server to the client. This field displays the MAC address of the client. Type Interface Name VLAN This field displays the client type, which can be: z Dynamic: The IP-to-MAC binding is generated dynamically. z Static: The IP-to-MAC binding is configured manually. Currently, static bindings are not supported. This field displays the device interface to which the client is connected. This field displays the VLAN to which the device belongs. Remaining Lease Time This field displays the remaining lease time of the IP address. Return to DHCP Snooping Configuration Task List. DHCP Snooping Configuration Example Network requirements As shown in Figure 3-6, a DHCP snooping device (Switch B) is connected to a DHCP server through GigabitEthernet 1/0/1, and to DHCP clients through GigabitEthernet 1/0/2 and GigabitEthernet 1/0/3. z Enable DHCP snooping on Switch B and configure DHCP snooping to support Option 82. Configure the handling strategy for DHCP requests containing Option 82 as replace. z Enable GigabitEthernet 1/0/1 to forward DHCP server responses; disable GigabitEthernet 1/0/2 and GigabitEthernet 1/0/3 from forwarding DHCP server responses. z Configure Switch B to record clients' IP-to-MAC address bindings in DHCP-REQUEST messages and DHCP-ACK messages received from a trusted port. Figure 3-6 Network diagram for DHCP snooping configuration Configuration procedure # Enable DHCP snooping. z Select Network > DHCP from the navigation tree, and then click the DHCP Snooping tab. Perform the following operation, as shown in Figure 3-7. 3-6

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3-6
Table 3-3
DHCP snooping user information configuration items
Item
Description
IP Address
This field displays the IP address assigned by the DHCP server to the
client.
MAC Address
This field displays the MAC address of the client.
Type
This field displays the client type, which can be:
Dynamic: The IP-to-MAC binding is generated dynamically.
Static: The IP-to-MAC binding is configured manually. Currently, static
bindings are not supported.
Interface Name
This field displays the device interface to which the client is connected.
VLAN
This field displays the VLAN to which the device belongs.
Remaining Lease Time
This field displays the remaining lease time of the IP address.
Return to
DHCP Snooping Configuration Task List
.
DHCP Snooping Configuration Example
Network requirements
As shown in
Figure 3-6
, a DHCP snooping device (Switch B) is connected to a DHCP server through
GigabitEthernet 1/0/1, and to DHCP clients through GigabitEthernet 1/0/2 and GigabitEthernet 1/0/3.
Enable DHCP snooping on Switch B and configure DHCP snooping to support Option 82.
Configure the handling strategy for DHCP requests containing Option 82 as
replace
.
Enable GigabitEthernet 1/0/1 to forward DHCP server responses; disable GigabitEthernet 1/0/2
and GigabitEthernet 1/0/3 from forwarding DHCP server responses.
Configure Switch B to record clients’ IP-to-MAC address bindings in DHCP-REQUEST messages
and DHCP-ACK messages received from a trusted port.
Figure 3-6
Network diagram for DHCP snooping configuration
Configuration procedure
# Enable DHCP snooping.
Select
Network
>
DHCP
from the navigation tree, and then click the
DHCP Snooping
tab. Perform
the following operation, as shown in
Figure 3-7
.