4000 Router Series Layer 3 - IP Services Configuration Guide

Task Command Remarks

Display information about the file that

stores DHCP snooping entries.

display dhcp snooping binding database

Available in any

view.

Clear DHCP snooping entries.

reset dhcp snooping binding { all | ip

ip-address [ vlan vlan-id ] }

Available in user

view.

Clear DHCP packet statistics on the

DHCP snooping device

(MSR2000/MSR3000).

reset dhcp snooping packet statistics

Available in user

view.

Clear DHCP packet statistics on the

DHCP snooping device (MSR4000).

reset dhcp snooping packet statistics [ slot

slot-number ]

Available in user

view.

DHCP snooping configuration examples

Basic DHCP snooping configuration example

Network requirements

As shown in Figure 27, configure the port Ethernet 1/1 connected to the DHCP server as a trusted port

and configure other ports as untrusted ports. Enable DHCP snooping to record clients' IP-MAC bindings

by reading DHCP-ACK messages received from the trusted port and DHCP-REQUEST messages.

Figure 27 Network diagram

Configuration procedure

# Enable DHCP snooping.

<Router> system-view

[Router] dhcp snooping enable

# Configure Ethernet 1/1 as a trusted port.

[Router] interface ethernet 1/1

[Router-Ethernet1/1] dhcp snooping trust

[Router-Ethernet1/1] quit

# Enable DHCP snooping to record clients' IP-MAC bindings on Ethernet 1/2.

[Router] interface ethernet 1/2