![background image](/i/zyxel/148476/zyxel-xs3900-48f/h/zyxel-xs3900-48f-213.png)
Chapter 24 IP Source Guard
XS3900-48F User’s Guide
213
24.6 ARP Inspection
Use this screen to look at the current list of MAC address filters that were created because the
Switch identified an unauthorized ARP packet. When the Switch identifies an unauthorized ARP
packet, it automatically creates a MAC address filter to block traffic from the source MAC address
and source VLAN ID of the unauthorized ARP packet. To open this screen, click Advanced
Application > IP Source Guard > ARP Inspection.
Figure 114
ARP Inspection Status
The following table describes the labels in this screen.
End VID
Enter the highest VLAN ID you want to manage in the section below.
Apply
Click this to display the specified range of VLANs in the section below.
VID
This field displays the VLAN ID of each VLAN in the range specified above. If you
configure the * VLAN, the settings are applied to all VLANs.
Enabled
Select Yes to enable DHCP snooping on the VLAN. You still have to enable DHCP
snooping on the Switch and specify trusted ports.
Note: The Switch will drop all DHCP requests if you enable DHCP snooping and there are
no trusted ports.
Option82
Select this to have the Switch add the slot number, port number and VLAN ID to DHCP
requests that it broadcasts to the DHCP VLAN, if specified, or VLAN. You can specify the
DHCP VLAN in the DHCP Snooping Configure screen. See
.
Information
Select this to have the Switch add the system name to DHCP requests that it broadcasts
to the DHCP VLAN, if specified, or VLAN. You can configure the system name in the
General Setup screen. See
. You can specify the DHCP VLAN in
the DHCP Snooping Configure screen. See
Apply
Click Apply to save your changes to the Switch’s run-time memory. The Switch loses
these changes if it is turned off or loses power, so use the Save link on the top
navigation panel to save your changes to the non-volatile memory when you are done
configuring.
Cancel
Click this to reset the values in this screen to their last-saved values.
Table 88
DHCP Snooping VLAN Configure (continued)
LABEL
DESCRIPTION
Table 89
ARP Inspection Status
LABEL
DESCRIPTION
Total number of
filters
This field displays the current number of MAC address filters that were created because
the Switch identified unauthorized ARP packets.
Index
This field displays a sequential number for each MAC address filter.
MAC Address
This field displays the source MAC address in the MAC address filter.
VID
This field displays the source VLAN ID in the MAC address filter.