3Com 2928 - Baseline Plus Switch PWR, User Manual

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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:
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.
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.
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 .