Dhcp Server Screening; Dhcp Server Screening Port Settings - D-Link xStack Reference Manual

xStack® DGS-3120 Series Layer 2 Stackable Managed Switch Web UI Reference Guide

DHCP Server Screening

This function allows the user to not only to restrict all DHCP Server packets but also to receive any specified DHCP
server packet by any specified DHCP client, it is useful when one or more DHCP servers are present on the network
and both provide DHCP services to different distinct groups of clients.
The first time the DHCP filter is enabled it will create both an access profile entry and an access rule per port entry, it
will also create other access rules. These rules are used to block all DHCP server packets. In addition to a permit
DHCP entry it will also create one access profile and one access rule entry the first time the DHCP client MAC address
is used as the client MAC address. The Source IP address is the same as the DHCP server's IP address (UDP port
number 67). These rules are used to permit the DHCP server packets with specific fields, which the user has
configured.
When DHCP Server filter function is enabled all DHCP Server packets will be filtered from a specific port.

DHCP Server Screening Port Settings

The Switch supports DHCP Server Screening, a feature that denies access to rogue DHCP servers. When the DHCP
server filter function is enabled, all DHCP server packets will be filtered from a specific port.
To view this window, click Security > DHCP Server Screening > DHCP Server Screening Port Settings as shown
below:
Figure 8-53 DHCP Server Screening Port Settings window
The fields that can be configured are described below:
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