2 configuration dhcp snooping – CANOGA PERKINS 9175 Configuration Guide User Manual
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CanogaOS Configuration Guide
36-3
ip address 5.5.5.2/24
!
Check the dhcp service status
DUT#show services
Networking services configuration:
Service Name Status
============================================================
dhcp enable
Check the dhcp server group configuration
DUT#show dhcp-server
DHCP server group information:
============================================================
group 1 ip address list:
[1] 4.4.4.1
Show dhcp relay statistics to check the dhcp relay statistics
DUT#show dhcp relay statistics
DHCP relay packet statistics:
============================================================
Client relayed packets: 20
Server relayed packets: 20
Client error packets: 20
Server error packets: 0
Bogus GIADDR drops: 0
Bad circuit ID packets: 0
Corrupted agent options: 0
Missing agent options: 0
Missing circuit IDs: 0
36.2 Configuration DHCP Snooping
36.2.1 Overview
DHCP snooping is a security feature that acts like a firewall between untrusted hosts and
trusted DHCP servers. The DHCP snooping feature performs the following activities:
• Validate DHCP messages received from untrusted sources and filters out invalid
messages
• Build and maintain the DHCP snooping binding database, which contains
information about untrusted hosts with leased IP addresses
• Utilize the DHCP snooping binding database to validate subsequent requests
from untrusted hosts
Other security features, such as dynamic ARP inspection (DAI), also use information
stored in the DHCP snooping binding database. DHCP snooping is enabled on a
per-VLAN basis. By default, the feature is inactive on all VLANs. You can enable the
feature on a single VLAN or a range of VLANs. The DHCP snooping feature is
implemented in software basis. All DHCP messages are intercepted in the BAY and
directed to the CPU for processing.