ZyXEL Communications ZyXEL Dimension ES-2048 - Manual (Page 180)

Chapter 21 IP Source Guard
ES-2048 User’s Guide
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21.5 DHCP Snooping Configure
Use this screen to enable DHCP snooping on the Switch (not on specific VLAN), specify the
VLAN where the default DHCP server is located, and configure the DHCP snooping database.
The DHCP snooping database stores the current bindings on a secure, external TFTP server so
that they are still available after a restart. To open this screen, click Advanced Application >
IP Source Guard > DHCP Snooping > Configure.
Figure 91 DHCP Snooping Configure
The following table describes the labels in this screen.
Table 60 DHCP Snooping Configure
LABEL DESCRIPTION
Active Select this to enable DHCP snooping on the Switch. You still have to
enable DHCP snooping on specific VLAN and specify trusted ports.
Note: The Switch will drop all DHCP requests if you enable
DHCP snooping and there are no trusted ports.
DHCP Vlan Select a VLAN ID if you want the Switch to forward DHCP packets to
DHCP servers on a specific VLAN.
Note: You have to enable DHCP snooping on the DHCP
VLAN too.
You can enable Option82 in the DHCP Snooping VLAN Configure
screen ( Section 21.5.2 on page 183 ) to help the DHCP servers distinguish
between DHCP requests from different VLAN.
Select Disable if you do not want the Switch to forward DHCP packets to a
specific VLAN.