DGS-3700-12/DGS-3700-12G Series Layer 2 Gigabit Ethernet Switch User Manual
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DHCP 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 Screening Port Settings
as shown below:
Figure 5 - 12 DHCP Screening Port Settings window
The following parameters can be set:
Parameter Description
From Port / To Port
A consecutive group of ports may be configured starting with the selected port.
State
Choose
Enabled
to enable the DHCP server or
Disabled
to disable. The default is
Disabled
.
After setting the previous parameters, click
Apply
to allow your changes to be implemented. The
DHCP Port
Information Table
shows which ports are enabled or disabled for DHCP Sever Screening.
DHCP Offer Filtering
This function allows the user 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 source port number 67). These rules are used to
permit the DHCP server packets with specific fields, which the user has configured.
To view this window, click
Security > DHCP Server Screening > DHCP Offer Filtering
as shown below:
Figure 5 - 13 DHCP Offer Filtering window
The user may set the following parameters:
Parameter
Description
Server IP Address
The IP address of the DHCP server.
