Displaying And Maintaining Dhcp Snooping; Dhcp Snooping Configuration Examples; Dhcp Snooping Configuration Example - 3Com 4500G Family Configuration Manual

Displaying and Maintaining DHCP Snooping

Display DHCP snooping entries
Display Option 82 configuration information
on the DHCP snooping device
Display DHCP packet statistics on the
DHCP snooping device
Display information about trusted ports
Clear DHCP snooping entries
Clear DHCP packet statistics on the DHCP
snooping device

DHCP Snooping Configuration Examples

DHCP Snooping Configuration Example

Network requirements
As shown in
and to two DHCP clients through GigabitEthernet 1/0/2 and GigabitEthernet 1/0/3.
GigabitEthernet 1/0/1 forwards DHCP server responses while the other two do not.
Switch B records clients' IP-to-MAC address bindings in DHCP-REQUEST messages and
DHCP-ACK messages received from trusted ports.
Figure 4-3 Network diagram for DHCP snooping configuration
GE1/0/1
GE1/0/2
DHCP client
Configuration procedure
# Enable DHCP snooping.
<SwitchB> system-view
[SwitchB] dhcp-snooping
# Specify GigabitEthernet 1/0/1 as trusted.
[SwitchB] interface gigabitethernet 1/0/1
To do...
Figure 4-3, Switch B is connected to a DHCP server through GigabitEthernet 1/0/1,
DHCP server
Switch B
DHCP snooping
GE1/0/3
DHCP client
Use the command...
display dhcp-snooping [ ip
ip-address ]
display dhcp-snooping
information { all | interface
interface-type interface-number }
display dhcp-snooping packet
statistics
display dhcp-snooping trust
reset dhcp-snooping { all | ip
ip-address }
reset dhcp-snooping packet
statistics
4-7
Remarks
Available in any
view
Available in
user view