Operation Manual – DHCP
H3C S3100 Series Ethernet Switches
Chapter 2 DHCP Snooping Configuration
2-16
II. Network diagram
Eth1/0/2
Client B
Switch
DHCP Snooping
Client A
Eth1/0/1
Client C
Eth1/0/3
Eth1/0/5
DHCP Server
Figure 2-6
Network diagram for DHCP-snooping Option 82 support configuration
III. Configuration procedure
# Enable DHCP snooping on the switch.
<Switch> system-view
[Switch] dhcp-snooping
# Specify Ethernet1/0/5 as the trusted port.
[Switch] interface Ethernet1/0/5
[Switch-Ethernet1/0/5] dhcp-snooping trust
[Switch-Ethernet1/0/5] quit
# Enable DHCP-snooping Option 82 support.
[Switch] dhcp-snooping information enable
# Set the remote ID sub-option in Option 82 to the system name (sysname) of the
DHCP snooping device.
[Switch] dhcp-snooping information remote-id sysname
# Set the circuit ID sub-option in DHCP packets from VLAN 1 to “abcd” on Ethernet
1/0/3.
[Switch] interface Ethernet1/0/3
[Switch-Ethernet1/0/3] dhcp-snooping information vlan 1 circuit-id string
abcd