Dhcp Snooping Configuration Examples; Dhcp-Snooping Option 82 Support Configuration Example - 3Com 5500-EI PWR Install Manual

DHCP Snooping Configuration Examples

DHCP-Snooping Option 82 Support Configuration Example

Network requirements
As shown in Figure
1/0/1, Ethernet 1/0/2, and Ethernet 1/0/3 are respectively connected to Client A, Client B, and Client C.
Enable DHCP snooping on the switch.
Specify Ethernet 1/0/5 on the switch as a trusted port for DHCP snooping.
Enable DHCP-snooping Option 82 support on the switch and set the remote ID field in Option 82 to
the system name of the switch. Set the circuit ID sub-option to abcd in DHCP packets from VLAN 1
on Ethernet 1/0/3.
Network diagram
Figure 4-6 Network diagram for DHCP-snooping Option 82 support configuration
Configuration procedure
# Enable DHCP snooping on the switch.
<Switch> system-view
[Switch] dhcp-snooping
# Specify Ethernet 1/0/5 as the trusted port.
[Switch] interface ethernet 1/0/5
[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 ethernet 1/0/3
4-6, Ethernet 1/0/5 of the switch is connected to the DHCP server, and Ethernet
4-11