HP V1910 Switch Series User Manual

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DHCP snooping configuration
NOTE:
A DHCP snooping enabled device does not work if it is between the DHCP relay agent and DHCP
server, and it can work when it is between the DHCP client and relay agent or between the DHCP clien
t
and server.
HP recommends you not to to enable the DHCP client, BOOTP client, and DHCP snoopin
g
on the same
device. Otherwise, DHCP snoopin
g
entries may fail to be
g
enerated, or the BOOTP client/DHCP clien
t
may fail to obtain an IP address.
DHCP snooping overview
Functions of DHCP snooping
As a DHCP security feature, DHCP snooping can implement the following:
1. Recording IP-to-MAC mappings of DHCP clients
2. Ensuring DHCP clients to obtain IP addresses from authorized DHCP servers
Recording IP-to-MAC mappings of DHCP clients
DHCP snooping reads DHCP-REQUEST messages and DHCP-ACK messages from trusted ports to record
DHCP snooping entries, including MAC addresses of clients, IP addresses obtained by the clients, ports
that connect to DHCP clients, and VLANs to which the ports belong.
Ensuring DHCP clients to obtain IP addresses from authorized DHCP servers
If there is an unauthorized DHCP server on a network, DHCP clients may obtain invalid IP addresses and
network configuration parameters, and cannot normally communicate with other network devices. With
DHCP snooping, the ports of a device can be configured as trusted or untrusted, ensuring the clients to
obtain IP addresses from authorized DHCP servers.
 Trusted: A trusted port forwards DHCP messages normally.
 Untrusted: An untrusted port discards the DHCP-ACK or DHCP-OFFER messages received from any
DHCP server.

HP V1910 Switch Series Specifications

General

Brand	HP
Model	V1910 Switch Series
Category	Switch
Language	English